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http://en.wikipedia.org/wiki/Nielsen_BookScan http://en.wikipedia.org/wiki/Nielsen_BookScan (edited to add: is the canonical source of this kind of data)
by adw 16y ago
http://en.wikipedia.org/wiki/Nielsen_BookScan http://en.wikipedia.org/wiki/Nielsen_BookScan
(edited to add: is the canonical source of this kind of data)