Variations and Fugue on a Theme by Handel located. In other words, what gives unity to the variation set ... is not the theme as such, but rather a network of 'family resemblances', to use Wittgenstein's term, between the different variations." There are various opinions about the organization of the "Handel Variations". Hans Meyer, for example, sees the divisions as nos. 1–8 ('strict'), 9–12 ('free'), 13 ('synthesis'), 14–17 ('strict') and 18–25 ('free'), culminating, of course, in the fugue. William Horne emphasizes paired variations: nos. 3 and 4, 5 and 6, 7 and 8, 11 and 12, 13 and 14, 23 and 24. This helps him to group the
International Standard Book Number to full EAN-13, in 2005, eased migration to the <nowiki>ISBN-13</nowiki> in North America. International Standard Book Number The International Standard Book Number (ISBN) is a unique numeric commercial book identifier. Publishers purchase ISBNs from an affiliate of the International ISBN Agency. An ISBN is assigned to each edition and variation (except reprintings) of a book. For example, an e-book, a paperback and a hardcover edition of the same book would each have a different ISBN. The ISBN is 13 digits long if assigned on or after 1 January 2007, and 10 digits long if assigned before 2007. The method of