%% -*-BibTeX-*- @InProceedings{Groetschel1979b, author = "Martin Gr{\"o}tschel", editor = "Lothar Collatz and G. Meinardus and W. {Wetterling (Hrsg.)}", booktitle = "Numerische Methoden bei graphentheoretischen und kombinatorischen Problemen, Bd. 2, Tagung in Oberwolfach 1978", title = "Strong blocks and the optimum branching problem", volume = "46", publisher = "Birkh{\"a}user", address = "Basel", pages = "112--121", year = "1979", series = "ISNM International Series of Numerical Mathematics", classmath = "*05C20 90C05 05C40", language = "English", }