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@Book{            book:2144924,
  Author        = "Spiegel, Murray R and Stephens, Larry J.",
  date-added    = "2020-04-10 11:07:26 +0200",
  date-modified = "2020-04-10 11:07:26 +0200",
  Edition       = "6th",
  ISBN          = "978-1-26-001147-0",
  Publisher     = "McGraw-Hill",
  Series        = "Schaum's Outlines",
  Title         = "Statistics",
  URL           = "http://gen.lib.rus.ec/book/index.php?md5=CAB392F9AD11585A60FE4D590C5C0500",
  Year          = "2018",
  bdsk-url-1    = "http://gen.lib.rus.ec/book/index.php?md5=CAB392F9AD11585A60FE4D590C5C0500",
  File          = "(Schaum’s Outlines) Murray R Spiegel, Larry J. Stephens-Statistics-McGraw-Hill (2018) (0) - a - a.pdf"
}

@Book{ book:2144924, Author = "Spiegel, Murray R and Stephens, Larry J.", date-added = "2020-04-10 11:07:26 +0200", date-modified = "2020-04-10 11:07:26 +0200", Edition = "6th", ISBN = "978-1-26-001147-0", Publisher = "McGraw-Hill", Series = "Schaum's Outlines", Title = "Statistics", URL = "http://gen.lib.rus.ec/book/index.php?md5=CAB392F9AD11585A60FE4D590C5C0500", Year = "2018", bdsk-url-1 = "http://gen.lib.rus.ec/book/index.php?md5=CAB392F9AD11585A60FE4D590C5C0500", File = "(Schaum’s Outlines) Murray R Spiegel, Larry J. Stephens-Statistics-McGraw-Hill (2018) (0) - a - a.pdf" }