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@Book{            book:808131,
  Author        = "Walter G. Kelley, Allan C. Peterson",
  date-added    = "2021-01-20 17:48:09 +0100",
  date-modified = "2021-01-20 17:48:09 +0100",
  Edition       = "2nd",
  ISBN          = "012403330X,9780124033306",
  Publisher     = "Academic Press",
  Title         = "Difference equations: an introduction with applications, 2nd Edition",
  URL           = "http://gen.lib.rus.ec/book/index.php?md5=e690a3912ba9849b0a4283bb198f6939",
  Year          = "2001",
  bdsk-url-1    = "http://gen.lib.rus.ec/book/index.php?md5=e690a3912ba9849b0a4283bb198f6939",
  File          = "Difference equations an introduction with applications, 2nd Edition by Walter G. Kelley, Allan C. Peterson (z-lib.org) - a.pdf"
}

@Book{ book:808131, Author = "Walter G. Kelley, Allan C. Peterson", date-added = "2021-01-20 17:48:09 +0100", date-modified = "2021-01-20 17:48:09 +0100", Edition = "2nd", ISBN = "012403330X,9780124033306", Publisher = "Academic Press", Title = "Difference equations: an introduction with applications, 2nd Edition", URL = "http://gen.lib.rus.ec/book/index.php?md5=e690a3912ba9849b0a4283bb198f6939", Year = "2001", bdsk-url-1 = "http://gen.lib.rus.ec/book/index.php?md5=e690a3912ba9849b0a4283bb198f6939", File = "Difference equations an introduction with applications, 2nd Edition by Walter G. Kelley, Allan C. Peterson (z-lib.org) - a.pdf" }