@techreport{BorndoerferHoppmannKarbsteinetal.2018, author = {Ralf Bornd{\"o}rfer and Heide Hoppmann and Marika Karbstein and Niels Lindner}, title = {Separation of Cycle Inequalities in Periodic Timetabling}, institution = {ZIB}, address = {Takustr. 7, 14195 Berlin}, number = {18-16}, language = {eng}, year = {2018} }