@techreport{BorndoerferEisenblaetterGroetscheletal.1997, author = {Ralf Bornd{\"o}rfer and Andreas Eisenbl{\"a}tter and Martin Gr{\"o}tschel and Alexander Martin}, title = {Frequency Assignment in Cellular Phone Networks}, institution = {ZIB}, address = {Takustr. 7, 14195 Berlin}, number = {SC-97-35}, language = {eng}, year = {1997} }