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@Book{            Ritt:book:1932,
  Author        = "Ritt, Joseph Fels",
  date-added    = "2020-04-10 11:07:26 +0200",
  date-modified = "2020-04-10 11:07:26 +0200",
  ISBN          = "1406763039,9781406763034",
  Publisher     = "American Mathematical Society",
  Series        = "Colloquium publications",
  Title         = "Differential Equations From The Algebraic Standpoint",
  URL           = "http://gen.lib.rus.ec/book/index.php?md5=7c5fce448a924ef4bbf49806fd8c236b",
  Year          = "1932",
  bdsk-url-1    = "http://gen.lib.rus.ec/book/index.php?md5=7c5fce448a924ef4bbf49806fd8c236b",
  File          = "Differential Equations From The Algebraic Standpoint by Joseph Fels Ritt (z-lib.org) - a - a - a - a.pdf"
}

@Book{ Ritt:book:1932, Author = "Ritt, Joseph Fels", date-added = "2020-04-10 11:07:26 +0200", date-modified = "2020-04-10 11:07:26 +0200", ISBN = "1406763039,9781406763034", Publisher = "American Mathematical Society", Series = "Colloquium publications", Title = "Differential Equations From The Algebraic Standpoint", URL = "http://gen.lib.rus.ec/book/index.php?md5=7c5fce448a924ef4bbf49806fd8c236b", Year = "1932", bdsk-url-1 = "http://gen.lib.rus.ec/book/index.php?md5=7c5fce448a924ef4bbf49806fd8c236b", File = "Differential Equations From The Algebraic Standpoint by Joseph Fels Ritt (z-lib.org) - a - a - a - a.pdf" }