
@article{tarski41,
  author  = {Tarski, Alfred},
  title   = {On the calculus of relations},
  journal = {Journal of Symbolic Logic},
  volume  = {6},
  pages   = {73--89},
  year    = {1941},
}

@book{maddux06,
  author    = {Roger Maddux},
  title     = {Relation Algebras},
  volume    = {150},
  series    = {Studies in Logic and the Foundations of Mathematics},
  publisher = {Elsevier Science},
  year      = {2006},
}

@book{schmidt87,
  author    = {Gunther Schmidt and Thomas Str{\"o}hlein},
  title     = {Relationen und Graphen},
  publisher = {Springer},
  year      = {1987},
}

@article{armstrong14,
  author = {Alasdair Armstrong and Georg Struth and Tjark Weber},
  title  = {Programming and Automating Mathematics in the
                  {Tarski}-{Kleene} Hierarchy},
  note   = {To appear in Journal of Logic and Algebraic Programming},
  year   = {2014},
}
