Ian Lamont writes: "The Economist writes that self-publishing threatens the existence of the International Standard Book Number (ISBN) regimen, which is used to track and distribute printed books. Self-publishing of e-books has experienced triple-digit growth in recent years, and the most popular self-publishing platforms such as Amazon's Kindle Direct Publishing don't require ISBNs (Amazon assigns its own reference number to these titles). But Bowker, the sole distributor of ISBNs in the United States, sees an opportunity in self-publishing. The packages for independent authors are very expensive — Bowker charges $125 for a single ISBN, and $250 for ten. It also upsells other expensive services to new and naive authors, including $25 barcodes and a social widget that costs $120 for the first year. Laura Dawson, the product manager for identifiers at Bowker, insists that ISBNs are relevant and won't be replaced anytime soon: "Given how hard it is to migrate database platforms and change standards, I wouldn’t expect to replace the ISBN, simply because it is also an EAN, which is an ISO standard that forms the backbone of global trade of both physical and digital items. There are a lot of middlemen, even in self-publishing. They require standards in order to communicate with one another.""