@article{Grotendorst1991,
  author    = {Grotendorst, Johannes},
  title     = {A Maple package for transforming series, sequences and functions},
  series = {Computer Physics Communications. 67 (1991), H. 2},
  journal   = {Computer Physics Communications. 67 (1991), H. 2},
  isbn      = {0010-4655},
  pages     = {325 -- 342},
  year      = {1991},
  language  = {en}
}
@article{Grotendorst1990,
  author    = {Grotendorst, Johannes},
  title     = {Approximating functions by means of symbolic computation and a general extrapolation method},
  series = {Computer Physics Communications. 59 (1990), H. 2},
  journal   = {Computer Physics Communications. 59 (1990), H. 2},
  isbn      = {0010-4655},
  pages     = {289 -- 301},
  year      = {1990},
  language  = {en}
}
@article{WeberHekmatZimmermannetal.2004,
  author    = {Weber, Hans-Joachim and Hekmat, K. and Zimmermann, T. and Kampe, S.},
  title     = {Impact of tranexamic acid vs. aprotinin on blood loss and transfusion requirements after cardiopulmonary bypass: a prospective, randomised, double-blind trial / Hekmat, K. ; Zimmermann, T. ; Kampe, S. ; Kasper, S. M. ; Weber, H. J. ; Geissler, H. J. ; Meh},
  series = {Current Medical Research and Opinion. 20 (2004), H. 1},
  journal   = {Current Medical Research and Opinion. 20 (2004), H. 1},
  isbn      = {0300-7995},
  pages     = {121 -- 126},
  year      = {2004},
  language  = {en}
}
@book{Laack2001,
  author    = {Laack, Walter van},
  title     = {A better history of our world / Vol. 1. The universe},
  publisher = {van Laack},
  address   = {Aachen},
  isbn      = {978-3-8311-1490-0},
  pages     = {188 S.},
  year      = {2001},
  language  = {en}
}
@book{Laack2002,
  author    = {Laack, Walter van},
  title     = {A better history of our world / Vol. 2. Life},
  publisher = {van Laack},
  address   = {Aachen},
  isbn      = {978-3-8311-2597-5},
  pages     = {236 S.},
  year      = {2002},
  language  = {en}
}
@book{Laack2003,
  author    = {Laack, Walter van},
  title     = {A better history of our world / Vol. 3. Death},
  publisher = {van Laack},
  address   = {Aachen},
  isbn      = {978-3-936624-01-4},
  pages     = {276 S.},
  year      = {2003},
  language  = {en}
}
@book{Laack2000,
  author    = {Laack, Walter van},
  title     = {Key to Eternity / Walter van Laack. [Transl. by Anneliese Wolstenholme]},
  publisher = {van Laack},
  address   = {Aachen},
  isbn      = {978-3-8311-0344-7},
  pages     = {256 S.},
  year      = {2000},
  language  = {en}
}
@article{KraftHeerRetkowitz2008,
  author    = {Kraft, Bodo and Heer, Thomas and Retkowitz, Daniel},
  title     = {Algorithm and Tool for Ontology Integration Based on Graph Rewriting / Heer, Thomas ; Retkowitz, Daniel ; Kraft, Bodo},
  series = {Applications of Graph Transformations with Industrial Relevance / Third International Symposium, AGTIVE 2007, Kassel, Germany, October 10-12, 2007, Revised Selected and Invited Papers},
  journal   = {Applications of Graph Transformations with Industrial Relevance / Third International Symposium, AGTIVE 2007, Kassel, Germany, October 10-12, 2007, Revised Selected and Invited Papers},
  isbn      = {978-3-540-89019-5},
  pages     = {577 -- 582},
  year      = {2008},
  language  = {en}
}
@article{KraftHeerRetkowitz2008,
  author    = {Kraft, Bodo and Heer, Thomas and Retkowitz, Daniel},
  title     = {Incremental Ontology Integration / Heer, Thomas ; Retkowitz, Daniel ; Kraft, Bodo},
  series = {Proceedings of the 10th International Conference on Enterprise Information Systems : Barcelona, Spain, June 12 - 16, 2008 / organized by INSTICC, Institute for Systems and Technologies of Information, Control and Communication ... [Ed. by Jos{\´e} Cordeiro ...]},
  journal   = {Proceedings of the 10th International Conference on Enterprise Information Systems : Barcelona, Spain, June 12 - 16, 2008 / organized by INSTICC, Institute for Systems and Technologies of Information, Control and Communication ... [Ed. by Jos{\´e} Cordeiro ...]},
  publisher = {INSTICC},
  address   = {Setubal},
  pages     = {13 -- 28},
  year      = {2008},
  language  = {en}
}
@book{Laack2007,
  author    = {Laack, Walter van},
  title     = {To perceive the world with logic},
  publisher = {van Laack},
  address   = {Aachen},
  isbn      = {978-3-936624-08-3},
  pages     = {340 S. : Ill., graph. Darst},
  year      = {2007},
  language  = {en}
}