@inproceedings{Groetschel1976, author = {Martin Gr{\"o}tschel}, title = {{\"U}ber Graphen mit Kreisen, die gegebene Wege enthalten}, booktitle = {Proceedings in Operations Research}, editor = {J{\"u}rg Kohlas and Olaf Seifert and H. Zimmermann}, volume = {5}, pages = {119 -- 121}, year = {1976}, }