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@Book{            book:6703,
  Author        = "(ed.), Demidovich B.",
  date-added    = "2020-04-10 11:07:26 +0200",
  date-modified = "2020-04-10 11:07:26 +0200",
  Publisher     = "Mir",
  Title         = "Problems in mathematical analysis",
  URL           = "http://gen.lib.rus.ec/book/index.php?md5=fdb5cb8fcf6840e881adee893d2e65a0",
  Year          = "1970",
  bdsk-url-1    = "http://gen.lib.rus.ec/book/index.php?md5=fdb5cb8fcf6840e881adee893d2e65a0",
  File          = "Problems in mathematical analysis - a - a - a.pdf",
  file-2        = "Problems in mathematical analysis - a - a - a.djvu"
}

@Book{ book:6703, Author = "(ed.), Demidovich B.", date-added = "2020-04-10 11:07:26 +0200", date-modified = "2020-04-10 11:07:26 +0200", Publisher = "Mir", Title = "Problems in mathematical analysis", URL = "http://gen.lib.rus.ec/book/index.php?md5=fdb5cb8fcf6840e881adee893d2e65a0", Year = "1970", bdsk-url-1 = "http://gen.lib.rus.ec/book/index.php?md5=fdb5cb8fcf6840e881adee893d2e65a0", File = "Problems in mathematical analysis - a - a - a.pdf", file-2 = "Problems in mathematical analysis - a - a - a.djvu" }