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@Book{            book:9973,
  Author        = "Conway, John H. and Guy, Richard",
  date-added    = "2020-04-10 11:07:26 +0200",
  date-modified = "2020-04-10 11:07:26 +0200",
  Edition       = "Corrected",
  ISBN          = "9780387979939,0-387-97993-X",
  Publisher     = "Copernicus",
  Title         = "The book of numbers",
  URL           = "http://gen.lib.rus.ec/book/index.php?md5=64A88F46D1A1979FC3DC543920074901",
  Year          = "1996",
  bdsk-url-1    = "http://gen.lib.rus.ec/book/index.php?md5=64A88F46D1A1979FC3DC543920074901",
  File          = "The Book of Numbers (0) - a - a.djvu"
}

@Book{ book:9973, Author = "Conway, John H. and Guy, Richard", date-added = "2020-04-10 11:07:26 +0200", date-modified = "2020-04-10 11:07:26 +0200", Edition = "Corrected", ISBN = "9780387979939,0-387-97993-X", Publisher = "Copernicus", Title = "The book of numbers", URL = "http://gen.lib.rus.ec/book/index.php?md5=64A88F46D1A1979FC3DC543920074901", Year = "1996", bdsk-url-1 = "http://gen.lib.rus.ec/book/index.php?md5=64A88F46D1A1979FC3DC543920074901", File = "The Book of Numbers (0) - a - a.djvu" }