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@Book{            Wilf:generatingfunctionology:2005,
  Author        = "Wilf, Herbert S.",
  date-added    = "2020-04-10 11:07:26 +0200",
  date-modified = "2020-04-10 11:07:26 +0200",
  Edition       = "3",
  ISBN          = "1568812795,9781568812793",
  Publisher     = "A K Peters / CRC Press",
  Title         = "generatingfunctionology",
  URL           = "http://gen.lib.rus.ec/book/index.php?md5=27e3a1652619762993fce4d5d8fac148",
  Year          = "2005",
  bdsk-url-1    = "http://gen.lib.rus.ec/book/index.php?md5=27e3a1652619762993fce4d5d8fac148",
  File          = "generatingfunctionology.pdf",
  file-2        = "gfologyLinked2 (0) - a - a.pdf"
}

@Book{ Wilf:generatingfunctionology:2005, Author = "Wilf, Herbert S.", date-added = "2020-04-10 11:07:26 +0200", date-modified = "2020-04-10 11:07:26 +0200", Edition = "3", ISBN = "1568812795,9781568812793", Publisher = "A K Peters / CRC Press", Title = "generatingfunctionology", URL = "http://gen.lib.rus.ec/book/index.php?md5=27e3a1652619762993fce4d5d8fac148", Year = "2005", bdsk-url-1 = "http://gen.lib.rus.ec/book/index.php?md5=27e3a1652619762993fce4d5d8fac148", File = "generatingfunctionology.pdf", file-2 = "gfologyLinked2 (0) - a - a.pdf" }