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@Book{            book:1122291,
  Author        = "Simpson, Stephen G.",
  date-added    = "2021-04-30 19:58:17 +0200",
  date-modified = "2021-04-30 19:58:17 +0200",
  Edition       = "2nd",
  ISBN          = "978-0-521-88439-6,978-0-511-57985-1",
  Publisher     = "Cambridge University Press",
  Series        = "Perspectives in Logic",
  Title         = "Subsystems of Second Order Arithmetic",
  URL           = "http://gen.lib.rus.ec/book/index.php?md5=9085e826cd1783a5246ad0ac4f534725",
  Year          = "2009",
  bdsk-url-1    = "http://gen.lib.rus.ec/book/index.php?md5=9085e826cd1783a5246ad0ac4f534725",
  File          = "Subsystems of Second Order Arithmetic by Stephen G. Simpson (z-lib.org) - v.pdf"
}

@Book{ book:1122291, Author = "Simpson, Stephen G.", date-added = "2021-04-30 19:58:17 +0200", date-modified = "2021-04-30 19:58:17 +0200", Edition = "2nd", ISBN = "978-0-521-88439-6,978-0-511-57985-1", Publisher = "Cambridge University Press", Series = "Perspectives in Logic", Title = "Subsystems of Second Order Arithmetic", URL = "http://gen.lib.rus.ec/book/index.php?md5=9085e826cd1783a5246ad0ac4f534725", Year = "2009", bdsk-url-1 = "http://gen.lib.rus.ec/book/index.php?md5=9085e826cd1783a5246ad0ac4f534725", File = "Subsystems of Second Order Arithmetic by Stephen G. Simpson (z-lib.org) - v.pdf" }