There were also issues about custom taxes. A first outline agreement was reached between the U.S. and the European Union in December 1997. This agreement was followed by an international convention. The internet was decided a free trade area, i.e. without any custom taxes for software, films and digital books bought online. Material goods (books, CDs, DVDs) and services were subject to existing regulations, with collection of VAT (value added tax) for example, but with no additional custom taxes. On the footsteps of the Internet Bookstore, based in United Kingdom and the largest online bookstore in Europe, Amazon.com launched is Associates Program. As stated in a press release dated June 8, 1998: "The Amazon.com Associates Program allows website owners to easily participate in hassle-free electronic commerce by recommending books on their site and referring visitors to Amazon.com. In return, participants earn referral fees of up to 15 percent of the sales they generate. Amazon.com handles the secure online ordering, customer service, and shipping and sends weekly email sales reports. Enrollment in the program is free, and participants can be up and running the same day. Associates range from large and small businesses to nonprofits, authors, publishers, personal home pages, and more. The popularity of the program is reflected in the range of additions to the Associates Community in the past few months: Adobe, InfoBeat, Kemper Funds, PR Newswire, Travelocity, Virtual Vineyards, and Xoom." There were 60,000 "associates" in June 1998. Barnes & Noble, a leading U.S. bookseller, entered the world of e-commerce in 1997. Barnes & Noble had 481 stores nationwide in 1997, in 48 states out of 50, as well as 520 bookstores (B. Dalton stores) in shopping malls, and a catalog of 175,000 titles from 20,000 publishers. Barnes & Noble also published books under its own imprint for exclusive sale through its retail stores - and its nationwide mail-order catalogs. Barnes & Noble first launched its America OnLine (AOL) website in March 1997 - as the exclusive bookseller for the 12 million AOL customers -, before launching its own website, barnesandnoble.com, in May 1997. The site was offering reviews from authors and publishers, with a catalog of 630,000 titles available for immediate shipping, and significant discounts: 30% off all in-stock hardcovers, 20% off all in-stock paperbacks, 40% off select titles, and up to 90% off bargain books. Its Affiliate Network spread quickly, with 12,000 affiliate websites in May 1998, including CNN Interactive, Lycos and ZDNet.