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@Book{            book:1157084,
  Author        = "Heyting, Arend",
  date-added    = "2020-04-10 11:07:26 +0200",
  date-modified = "2020-04-10 11:07:26 +0200",
  Edition       = "3rd",
  ISBN          = "0720422396, 9780720422399",
  Publisher     = "North-Holland Pub. Co",
  Series        = "Studies in logic and the foundations of mathematics",
  Title         = "Intuitionism: An introduction",
  URL           = "http://gen.lib.rus.ec/book/index.php?md5=274e9615666f709d55cc4da83ee224a2",
  Year          = "1971",
  bdsk-url-1    = "http://gen.lib.rus.ec/book/index.php?md5=274e9615666f709d55cc4da83ee224a2",
  File          = "[Arend\_Heyting]\_Intuitionism\_An\_introduction(b-ok.xyz) (0) - a - a.pdf"
}

@Book{ book:1157084, Author = "Heyting, Arend", date-added = "2020-04-10 11:07:26 +0200", date-modified = "2020-04-10 11:07:26 +0200", Edition = "3rd", ISBN = "0720422396, 9780720422399", Publisher = "North-Holland Pub. Co", Series = "Studies in logic and the foundations of mathematics", Title = "Intuitionism: An introduction", URL = "http://gen.lib.rus.ec/book/index.php?md5=274e9615666f709d55cc4da83ee224a2", Year = "1971", bdsk-url-1 = "http://gen.lib.rus.ec/book/index.php?md5=274e9615666f709d55cc4da83ee224a2", File = "[Arend_Heyting]_Intuitionism_An_introduction(b-ok.xyz) (0) - a - a.pdf" }