Lower bounds for the relative greedy algorithm for approximating Steiner trees. - Stefan Hougardy; Stefan Kirchner (Networks, 2006)

An FPTAS for Computing the Similarity of Three-Dimensional Point Sets. - Stefan Kirchner (Int. J. Comput. Geom. Appl., 2007)

Untere Schranken für Steinerbaumalgorithmen und die Konstruktion von Bicliquen in dichten Graphen - Stefan Kirchner (2008)