Marc Benkert Joachim Gudmundsson Christian Knauer Esther Moet René van Oostrum Alexander Wolff A Polynomial-Time Approximation Algorithm for a Geometric Dispersion Problem. 166-175 2006 conf/cocoon/2006 COCOON http://dx.doi.org/10.1007/11809678_19 db/conf/cocoon/cocoon2006.html#BenkertGKMOW06