%% -*-BibTeX-*- @InProceedings{BorndoerferLiebchen2008, author = "Ralf Bornd{\"o}rfer and Christian Liebchen", editor = "J{\"o}rg Kalcsics and Stefan Nickel", booktitle = "Operations Research Proceedings 2007", title = "{When Periodic Timetables are Suboptimal}", publisher = "Springer Verlag, Berlin", pages = "449--454", year = "2008", note = "{ZIB} Report 07-29 available at \url{http://opus.kobv.de/zib/volltexte/2007/1056/}", language = "English", }