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  interhash = {e15113f443dfe1054256c34bd365a4ad},
  intrahash = {3cbe3059391ae0f543c448701949ddbc},
  school = {Technische Universität Dresden},
  title = {Die Struktur der Monoide binärer Relationen auf endlichen Mengen},
  type = {Diplomarbeit},
  url = {http://www.kde.cs.uni-kassel.de/pub/pdf/jaeschke2005struktur.pdf},
  year = 2005
}

@article{yang69,
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  interhash = {3091b16dcb62c8a3e7cbe0e7505d7331},
  intrahash = {0ba5eb63a0676e360e42c305a9297c4a},
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  volume = 22,
  year = 1969
}

@article{zaretski63,
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  interhash = {430f0d7da2f2497b1e17285ea9540ae4},
  intrahash = {89cada18428af1a3bba8a6e4efd8be16},
  journal = {Matematiceskij Sbornik},
  note = {(russisch)},
  pages = {291-305},
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  year = 1963
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@article{schein76,
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  interhash = {f569baaa08e9eab441e3786c088193dd},
  intrahash = {6790c6e1d10a6b12b5556342a9681413},
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@article{schein70,
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  interhash = {341ee2f65ff1940a18d395f2cf5eadd4},
  intrahash = {100395cf400ac7fa3109ce84ae9bcdb8},
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  year = 1970
}