Category Archives: Sociotechnical

Yet Another Bitcoin Use Case: microtransactions

With the usual drumbeat of bad news continues, fraud, price manipulation, opaque actors, extortion, and just plain “oopsies”, a disinterested observer can be forgiven for wondering if the end is near for crypotcurrencies.

Bitcoin itself is increasingly controlled by giant mining combines who effectively control the Bitcoin network. This situation was assumed to be impossible in the original Nakmoto design [1], but here it is. And it is leading to a catastrophic crackup (AKA the “hard fork”), possibly as soon as August.

Meanwhile, this blog is ticking off the long list of supposed use cases for Bitcoin and blockchains. Supply chains?  Yes.  Remittance? Not on a public blockchain. Local currencies? Nope. Identity? Mostly not.

This week there is yet another use case that isn’t happening: Microtransactions.

From the start, it was imagined that Bitcoin technology could support transactions of any size, down to fractions of a penny. The cost of doing a transaction could be small, possibly even zero, and if so, then there is no reason not to do lots of tiny transactions. This would open the way to all kinds of new business (pay as you go for web content, metered use of services, etc.) including automatic management of IoT resources.

How is this admittedly exciting use case holding up?

Chuan Tian reports in Coindesk that “SatoshiPay to Stop Using Bitcoin Blockchain for MicropaymentsStoshiPay is a nicely developed concept that has, for instance, a plugin for WordPress that would let me charge you a tenth of a penny (in Bitcoin) to read this deathless prose.

Their business model is to take 10% of every transaction—when you paid me, they get 1/100 of a penny.

The original approach was to just use Bitcoin, putting the transactions on the Bitcoin blockchain. Even bundling a bunch of them, these are small transactions, so the cost of pushing them out to the ledger obviously has to be small enough for the 10% cut to be profitable.

As Tian points out, the “essentially zero” transaction costs seen even two years ago are long gone, and more than one company has abandoned microtransactions with Bitcoin. At $2 and more per transaction, it is economically infeasible to implement microtransactions directly in Bitcoin. (By the way, these transaction costs for Bitcoin are now in the range with conventional financial systems.)

Why has this happened? Congestion.

The same scaling issues that are threatening to crack Bitcoin into multiple rival networks have pushed transaction fees higher and higher. The big players who are collect these fees (their entire business model is to collect these fees) have blocked engineering changes that would likely reduce congestion, and lower fees.

It is possible that transaction fees might go down, who knows. But the fact is there isn’t any good reason why you need to use the public ledger to implement microtransactions at all. So companies are moving to other technology.

SatoshiPay is said to be moving to IOTA, which is a blockchain-inspired system targeting the Internet of Things. IOTA implements a cryptographically secured peer-to-peer network, with their own protocol and data structures. They argue that transaction fees will be very low, or even zero.

Actually, the IOTA protocol and data structures are completely different from Nakamoto [2]. IOTA is based on familiar concepts used in large scale data systems, with a peer to peer twist inspired by Bitcoin. They use cryptography and the idea of consensus, but in a way that allows a lot more throughput, along with other interesting features such as smooth offline operation (i.e., you can cut off part of the transactions and merge them back later).

There are some funky things about the protocol (e.g., there is a knob for how confident you want to be about the validity of the transaction tree) but there are no miners and therefore no transaction fees.

IOTA aims to do IOT things, smart machines bargaining with each other. (No puny humans involved!) They call thing the Economy of Things or something like that. But what they have built should also be good for something like SatoshiPay.

As in many Bitcoin use cases, people using SatoshiPay or services that use it will never notice the transaction technology behind the scenes.

Will we finally see digital microtransactions? I dunno. But it won’t be on the public Bitcoin blockchain, that seems clear.

So this use case for blockchain might come true, but, as IOTA puts, with No Blocks and No Chains.

Inspired by Bitcoin, yes.

But implemented by more sophisticated technology, designed for this use case.


  1. Satoshi Nakamoto, Bitcoin: A Peer-to-Peer Electronic Cash System. 2009. http://bitcoin.org/bitcoin.pdf
  2. Dominik Schiener, A Primer on IOTA (with Presentation), in IOTA Blog. 2017. https://blog.iota.org/a-primer-on-iota-with-presentation-e0a6eb2cc621
  3. Chuan Tian,  SatoshiPay to Stop Using Bitcoin Blockchain for Micropayments Coindesk.July 17 2017, http://www.coindesk.com/satoshipay-stop-using-bitcoin-blockchain-micropayments/

 

 

Cryptocurrency Thursday

Freelancer’s Toolkits?

The members who are “managed” by cool coworking software are mainly freelancers and independent contractors. These workers rent their workplace, and bring their own tools. So what is in their tool box?


Michael Katz has some suggestions for what you should have [1] .

Actually, his list are pretty simple, and mostly about being organized, getting “more efficient we can get managing repeatable, often mundane aspects of our work”.

  • Directions to my office
  • Standardized cards (e.g., “Thank you for the referral”)
  • Service descriptions (i.e., what you do)
  • New client questionnaire
  • Newsletter sign-up form

I note that all of these things are non-digital though all of them can be implemented in digital forms. In fact, every one of these ideas predate the ubiquitous internet.  They are about good business practices and relationships, not about technology.


Jeriann Ireland offers another take on this question, suggesting “The essential toolkit for minimalist (or broke) freelancers[2].

  • A Ready-to-Go Resume Template (and use LinkedIn to get it out there
  • A Decent Phone Plan (with call waiting)
  • A Dedicated Work Space (and separate computers and accounts)

This is a good list, and definitely a sound foundation.

His discussion of the “dedicated” workspace captures the essential psychology “Whether it’s a home office, a shared office space, or even a corner in your home, have a place where you only store work-related paperwork and itemsNaturally, “a dedicated workspace” might be membership in a local coworking space.

(I did raise an eyebrow at the comment that this is “the same concept as not spending non-sleeping time in your bed.”  Hmm.  I should never do anything in bed except sleep?)


Anyway, together these articles make clear that much of the challenge of freelancing is to be well organized, and to have a clear understanding of your own work processes.

“Templates” seem to be an important thing.  Basically, a template represents your understanding of how you work, and, as Katz puts it, the mundane and repeatable aspects.

I think this is a good point. Furthermore, the templates these guys mention most prominently are the “scripts” used for finding gigs and making contracts. There are other repeatable processes, such as billing, but connecting with new clients needs to be personal—so you need customized conversations.  

All this sounds like work!

Worse, it sounds exactly like “looking for a job”—which it is.  Gig workers have to really, really good at job hunting because they have to do it all the time. 

(Yet another reason I’ll never be a good Freelancer:  I absolutely hate, hate, hate job hunting.)


1. Jeriann Ireland, The essential toolkit for minimalist (or broke) freelancers, in Freelancers Union Blog. 2017. https://blog.freelancersunion.org/2017/07/07/are-you-a-freelancer-or-entrepreneur-2/

2. Michael Katz,, What’s in your tool chest?, in Freelancers Union Blog. 2017. https://blog.freelancersunion.org/2017/07/13/whats-in-your-tool-chest-2/

What is Coworking? It’s Partly About Office Management

Coworking spaces have emerged as one of the places where independent workers and small startups choose to work

Coworking is enabled by ubiquitous digital technology, which makes it possible for workers to “bring your own device”, and to work from pretty much anywhere.

The same technology has enabled office managers to operate not only anywhere, but at very small scales. From the point of view of the operator, the challenge of coworking is to be able to slice up workspace into one worker pieces, and very short time periods. Some coworking spaces are willing to rent a single desk for an hour at at time.

This granularity, and a desire to offer an array of packages, means that the office management must be extremely efficient and inexpensive. These processes have been automated for decades, of course, But now there are an increasing number of packages designed for the lowest budget operations, including coworking spaces.

Not only can workers work anywhere, it’s pretty easy to set up almost any space to be a rental workspace.

For example, Andy Alsop of “The Receptionist.com” (maker of office management products) wrote about the “5 Best Coworking Office Space Management Software Solutions [1] .His list gives us an idea of the tasks that are commonly needed.

The five products listed may be a bit out of date, there will surely be many more entries in the intervening years.

But the important thing is, what do coworking space operators need?

The basic core is managing memberships and payments. The latter is a straightforward billing/invoicing task. The former combines elements of property leasing with customer relations, and different tools offer different features for this.

Nexudus (one of the biggest players) manages stuff like events, newsletters, and also printers and so on. Optix also has member-to-member messaging (redundant with Facebook etc.?) and a market for desk space. Coworkify has sales and marketing features (i.e., for recruiting members to fill the desks). Happy Desk has wifi network management and door access features.

All of the systems are designed to be sold or leased at low cost to even the smallest operator.

I note that this article is in the blog of The Receptionist, a company that makes “The Receptionist for iPad”, a versatile, effective and easy-to-use visitor management system available”. This suite of features includes annoying stuff like logging visitors to your office, integrated with deeper annoying features that connect these logs with security or sales data bases. All on an iPad connected to cloud services.

Overall, it is clear that complex business office processes are available to pretty much anyone.

In the case of the products that are specialized for coworking, the business features are combined with social features (e.g., mail and chat groups), PR stuff (event management, “customer relationship” stuff), and technical managements (wifi, doors, printers).

Phew!

This job is harder than I realized.

But the best thing about these products, to my mind, is that they enable a good community leader to provide professional quality business services with relatively little effort. This frees time and energy for the most important part, schmoozing, connecting, teaching, and listening.


  1. Andy Alsop, 5 Best Coworking Office Space Management Software Solutions, in The Receptionist – Blog. 2015. https://thereceptionist.com/5-best-coworking-space-management-software-solutions/

 

What is Coworking?

Note:  please stay tuned for my new ebook, “What is Coworking”, coming in 2017.

Blockchain for Local Identity?

As soon as I declare that blockchain technology is unsuited for two use cases, Identity and local currency , Wolfie Zhao reports in Coindesk that the Swiss city of Zug is going to have a local ID service using a blockchain.

Oops. These use cases are still open, or at least not as dead as I said.

Of course, there is a difference between a local currency and a local ID service. The former needs to interact with conventional financial systems, the latter needs to interact with conventional ID systems. The press release indicates that digital IDs are not well developed in Switzerland, though I’m sure that digital banking works great.

Similarly, there is a difference between a global ID system, with secure digital passports for everyone including refugees and repressed populations, and a digital ID issued by a city. For that matter, the city is Swiss, which means it already has a well developed national ID system to build on.

So this isn’t quite the use cases I considered earlier.

What it is, is an intersection of them, a simpler problem and a well organized local government. Perhaps this is a favorable “corner” of the use cases, where blockchain will work well.


So far as I can tell, the rationale for this system is that Switzerland has a personal ID system (which I’m sure is quite rigorous and efficient), but digital versions of the IDs have not been successful. Blockchain technology is a way to securely associate a cryptokey with a particular ID. The blockchain is intended to make it possible for digital apps to quickly and cheaply confirm IDs.

Sure. This can work.

We’ll see how well it works. Is there enough need for this sort of crypto ID, and does it work well enough to be useful?   I don’t know, we’ll find out.


I note that blockchain is being used for a tiny part of the problem. As the press release makes clear, citizens must go to a city office to prove their identity and then are issues a digital key. This process is the hard part, and blockchain does nothing to support this service.

We want a single electronic identity – a kind of digital passport – for all possible applications. And we do not want this digital ID to be centralized at the city, but on the blockchain.” (Dolfi Müller, quoted in [2])

It is ironic to see the proponents of this system talk about how this is a “decentralized” solution. What they mean by that is that the part of the process where digital IDs are looked up is “decentralized”, particularly compared to previous systems that have attempted to implement the service with a database.

Essentially, the city doesn’t want to run a database with a secure public interface. Fair enough.

To a certain extent, they are also boasting about the local city’s initiative, too, though IDs issued by one city may have limited use elsewhere. Ethereum runs everywhere, but Zug IDs may not be trusted anywhere outside Zug.

I suspect, though, that Zug is issuing IDs based on Swiss national credentials. In that case, IDs issued in Zug are great throughout Switzerland. These are, of course, centralized IDs in that case.

Looking up IDs is a decentralized problem, but issuing IDs demands trust, and a web of trust between authorities. If every city in Switzerland issues its own crypto IDs, even using the same Federal ID, it will be chaos.


Finally, I have to say, “Ethereum? Really?”

I’m rather surprised that anyone would try to build a trusted system using the catastrophically messed up Ethereum technology. But they probably use Microsoft Windows, too. Massively clever cryptography running on wobbly, hackable software infrastructure.

Anyway, we’ll see how this works out.


  1. Stadtverwaltung Zug. Blockchain-Identität für alle Einwohner. 2017, http://www.stadtzug.ch/de/ueberzug/ueberzugrubrik/aktuelles/aktuellesinformationen/?action=showinfo&info_id=383355.
  2. Wolfie Zhao, Swiss City Announces Plan to Verify IDs Using Ethereum Coindesk.July 7 2017, http://www.coindesk.com/swiss-city-verify-id-ethereum/

 

Cryptocurrency Thursday

“Games For Change” 2017 Student Challenge

And speaking of mobile apps with a social purpose….

The upcoming annual Games For Change (G4C) meeting has a lot of interesting stuff, on the theme “Catalyzing Social Impact Through Digital Games”. At the very least, this gang is coming out of the ivory tower and up off their futons, to try to do something, not just talk about it.

Part of this year’s activities is the Student Challenge , which si a competition that

“invites students to make digital games about issues impacting their communities, combining digital storytelling with civic engagement.

This year’s winners were announced last month, from local schools and game jams in NYC, Dallas, and Pittsburg. (Silicon Valley, where were you?) Students were asked to invent games on three topics,

  • Climate Change (with NOAA),
  • Future Communities (with Current by GE), and
  • Local Stories & Immigrant Voices (with National Endowment for the Humanities).

Eighteen winners were highlighted.

The “Future Cities” games mostly are lessons on the wonders of “smart cities”, and admonitions to clean up trash. One of them has a rather compelling “heart beat” of Carbon emissions, though the game mechanics are pretty obscure, doing anything or doing nothing at all increases Carbon. How do I win?

The “Climate Change” also advocates picking up trash, as well as planting trees. There is also a quiz, and an Antarctic Adventure (though nothing even close to “Never Alone”)

The “local stories” and “immigrant stories” tell stories about immigrants, past and present. (This kids are from the US, land of immigration.) There are two alarming “adventures” that sketches how to illegally enter the US, which is a dangerous undertaking with a lot of consequences. Not something I like to see “gamified”.

Overall, the games are very heavy on straight story telling, with minimal game-like features. Very much like the “educational games” the kids no doubt have suffered through for years. And not much like the games everyone really likes to play. One suspects that there were teachers and other adults behind the scenes shaping what was appropriate.

The games themselves are pretty simple technically, which is inevitable given the short development time and low budgets. The games mostly made the best of what they had in the time available.

I worry that these rather limited experiences will give the students a false impression of both technology and story telling. The technology used is primitive, they did not have realistic market or user testing, and the general game designs are unoriginal. That’s fine for student projects, but not really a formula for real world success, and has little to do with real game or software development.

Worse, the entire enterprise is talking about it. One game or 10,000 games that tell you (again) to pick up trash doesn’t get the trash picked up. If you want to gamify neighborhood clean up, you are going to need to tie it to the actual physical world, e.g., a “trashure hunt”, with points for cleaning up and preventing litter.

These kids did a super job on their projects, but I think the bar was set far too low. Let’s challenge kids to actually do something, not just make a digital story about it. How would you use game technology to do it? I don’t know. That’s what the challenge is.


  1. Games for Change, Announcing the winners of the 2017 G4C Student Challenge, in Games For Change Blog. 2017. http://www.gamesforchange.org/2017/07/announcing-the-2017-g4c-student-challenge-winners/

 

“Identity” on the Blockchain?

For the past few years, cryptocurrency and blockchain enthusiasts have been touting a variety of use cases for these technologies, suggesting that they will disrupt/revolutionize pretty much everything [2]. It’s a floor wax and a desert topping!

With time, we are sifting through these use cases, discovering which ones are more realistic.

The most successful uses to date are, unfortunately, extralegal commerce and cybercrime.  Other areas that appear promising are supply chains  and other business to business cases. In also seems likely that private blockchains may well disrupt FINTECH, and eliminate hundreds of thousands of jobs.

What haven’t panned out yet are the benefits for regular folks and the imagined benefits for the world’s poorest.

It is readily apparent that blockchain-based technology isn’t necessarily the right way to do community currencies and similar projects.  Cryptocurrency has made surprisingly little inroads into “the remittance problem”. For that matter, cryptocurrency has made little inroads for real world commerce, mainly because it solves problems that consumers don’t actually care about. (Most people don’t care about the innards of their digital payment systems.)

This month the ID2020 project summit gives reason to think that blockchain is also not a particularly useful technology for “identity”.

ID2020 is an international group dedicated to helping people who lack formal identity papers. This is a significant problem for refugees and others, and it’s quite reasonable to try to create portable digital documentation.

“1.1 BILLION PEOPLE LIVE WITHOUT AN OFFICIALLY RECOGNIZED IDENTITY”

I’m rather baffled by why this is called an ”identity’ problem, which it is mostly an “official recognition” problem.

Michael del Castillo comments in Coindesk, “Identity without the Blockchain? Skepticism Grows for Once-Hot Use Case”. Essentially, the ID2020 people aren’t convinced that blockchain technology is the solution, or at least, the only solution.

I don’t know exactly what their thinking is, but I suspect that a key point is that credentials are all about trust, and in fact, trust in third parties. The importance of credentials aren’t that you can prove that you are who you say you are, but that you can prove to someone that a mutually trusted party says you are who you say you are.

“Trustless” blockchain systems offer little to help provide these proofs. Decentralized blockchains are certainly cheap and easy ways to reliably pass around such certificates, but they don’t address the hard part, which is creating them in the first place.

Identity problems of rich people

There is a second “identity” use case for blockchains, and that is portable and flexible digital identities, i.e,, control of personal information on line. The idea is to make it possible for people to access digital services without having all their information linked. This is truly an important challenge, though, again, I wouldn’t call it a problem of “digital identity” per se, it’s more of an information control problem.

This use case is lumped with the passport issues  above because the same technology could, in principle, solve both. If we had a good way to exchange verifiable cryptographically shielded certificates, we could use them to, say, access services without a universal ID number.

As del Castillo says,

In theory, those users would own their own identities, as opposed to Facebook, Google, the government, or any number of organizations, all of whom want to keep a record of – and profit from – that data.

This is an interesting statement of the problem and perceived solution.

He lumps all organizations, private, public, and “other”, which glosses over important differences, which is intellectually and politically dubious.

The Drivers License folks keep a record of you because they need to certify your qualifications to drive. Doctors keep medical records for obvious reasons. And so on. There are many reasons why organizations keep your history.

On the other hand, advertising companies like Google and Facebook, keep information on you to make money by “selling” you. So do numerous other companies.

Solving this problem is difficult, and not only because there is a lot of money begin made, and the powers-that-be don’t want to be disrupted, thank you very much.

The technical problems are actually quite difficult. Figuring out what sort of information needs to be exchanged and developing secure ways to present just what you need to and no more is very difficult. Furthermore, this process involves—wait for it—trust. No matter how clever the credential scheme, the credentials have to come from somewhere in the first place, and have to be accepted where you need them.

Blockchain technology is a good way to pass around cryptographically shielded credentials. But, again, it doesn’t help the process of obtaining credentials in the first place. If you can create a good system for digital credentials, a blockchain will certainly be one of the places you use it. But the blockchain alone doesn’t solve the problem.


I’ll add one more pedantic point. Some of the enthusiasm for blockchains is actually based on the extreme usefulness of public key cryptography, which will definitely, for sure, be the critical piece in these digital systems. But you can use PKI with lots of different architectures, “centralized” and “decentralized”, and with many different business models. Just because cryptographic signatures address a use case, it isn’t necessarily true that blockchains are relevant.


  1. Michael del Castillo, Identity without the Blockchain? Skepticism Grows for Once-Hot Use Case. Coindesk.June 22 2017, http://www.coindesk.com/identity-without-blockchain-skepticism-grows-hot-use-case/
  2. Don Tapscott and Alex Tapscott, Blockchain Revolution: How the Technology Behind Bitcoin is Changing Money, Business, and the World, New York, Portfolio/Penguin, 2016.

 

Cryptocurrency Thursday

Local Digital Currency in Spain: No Blockchain Involved

Cryptocurrency enthusiasts cite many potential benefits of Nakamotan cryptocurrencies (e.g., see [5]). Many of the claims are nonsense (e.g., many of the alleged virtues of “trustless” systems) or based on emotional anti-authority appeals.

Some of the more compelling use cases, though, are about empowering the 99.999%, by enabling access to low cost financial services for everyone, and generally enhancing local economies. These are attractive goals, though little progress has been made to achieve them.

My own view is that blockchain-based systems can be used for such purposes, but are neither necessary nor sufficient. There are better ways to skin that cat.


A case in point are the growing number of local currencies. For example, Aaron Fernando reports on the establishment of a local currency, the grama, in Santa Coloma de Gramanet, Spain. This purely digital currency is created by the local government and is pegged to the official Euro, However, the digital tokens have additional features designed to encourage them to circulate in the local area, rather than immediately fly away to distant banks or corporations.

The currency is only issued in the city, and some local business offer discounts. Most importantly, the currency has a “use by” date, or rather, a “use until” date.

a 5 percent penalty is imposed on exchanging gramas to euros before 45 days, with no exchange penalty after 45 days.

The whole idea is to maximize the value of local spending to the local community.

Personally, I like the idea.

I always try to patronize locally owned businesses, and hire local contractors whenever possible, so it is nice to see a digital system try to enhance this socially positive behavior.

Whether this sort of algorithmic game will have a big economic impact or not isn’t clear to me. For one thing, it’s kind of difficult to draw a boundary around a “local” economy. And however you draw the line, a city or locality is never a closed system.

But it’s better to try something, than to do nothing except complain.

I note that Spain certainly has been brutally punished by using the German controlled Euro [4]. Add in the longstanding nationalist aspirations of Catalonia, and there is a lot of motivation for local economic self-determination, and plenty of justification for experimentation.

The grama is inspired by the Bristol Pound and other contemporary local digital currencies. For that matter, local currencies predate digital technology, including famous case such as Ithaca NY.

So what does the grama tell us about blockchains and cryptocurrency?

I haven’t found much of a technical description of the Santa Coloma grama. I’m pretty sure they are connected to the conventional financial system, though I don’t understand the details.

If they are using a Nakmotoan blockchain, they never say so. I’m pretty suer they have nothing to do with any blockchain, and there is no reason why they would use a blockchain or Nakamoto-style “mining”.. The currency is baccked by Euros (a hated “fiat” currency) and issued by the local city government.

The Bristol Pound is not blockchain based, either, so far as I can tell. Nor are the other local currencies from Qoin.

In short, these leading local currencies could use blockchains, but do not. Why not?

You certainly could use a blockchain, or Bitcoin, or some other cryptocurrency to implement a local digital currency like the grama. But I think there is little reason to do so, and many reasons not to.

In these local currencies, the digital technology is designed to enhance face-to-face interactions among local people, which are inherently trustworthy. Furthermore, the local currency enhances trust in local institutions and businesses, and discourages dealing with anonymous, untrustworthy outsiders.

A local currency is designed to encourage face-to-face, non-anonymous transactions.

A local currency is trusted because it relies on personal relations.

Blockchain technology, in contrast, is designed to move money around the world with little friction, sucking money away from local economies. Transactions are not only not face-to-face, they are partly anonymous. And furthermore, public blockchains such as Bitcoin or Ethereum are “decentralized”, and have no one responsible for them, let alone no local control over decision making.

Cryptocurrencies are the opposite of “local currencies”.

“Decentralized” blockchains are the opposite of “locally controlled” systems.

Cryptcocurrencies are “trustless”, which is antithetical to local solidarity.

The bottom line is that digital technology, including cryptographic signatures, definitely are a good technology for empowering local communities.

However, blockchains in general, and global cryptocurrencies specifically, are really not the right technology for local currencies, and probably not for empowering people in any way.

The key to success for this kind of system is good interface design, local organizing (Santa Coloma has participation from local government and over 100 local businesses), and the backing of the public. It could have a blockchain inside or not—users would never know the difference.

If blockchains are not the right technology for a local currency, then it is worth asking if blockchains are the right technology for any kind of local self-government.

My own view is that, to the degree that blockchain-based systems encourage offshore finance and “autonomous” transactions, they are the perfect tools for the exploitation of local communiities, and likely to be very destructive of local economies.


  1. Bristol Pound Community Interest Company. The Bristol Pound – Our City, Our Money. 2017, https://bristolpound.org/.
  2. Aaron Fernando, How One City in Spain Launched a Local Currency Sharable.June 8 2017, http://www.shareable.net/blog/how-one-city-in-spain-launched-a-local-currency
  3. Qoin. Qoin – Money That Matters. 2017, http://www.qoin.com/.
  4. Joseph E. Stiglitz, The Euro: How A Common Currency Threatens the Future of Europe, New York, W. W. Norton& Company, 2016.
  5. Don Tapscott and Alex Tapscott, Blockchain Revolution: How the Technology Behind Bitcoin is Changing Money, Business, and the World, New York, Portfolio/Penguin, 2016.

 

Cryptocurrency Thursday