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@article{CMH_1959__33_139175, author = {Woldemar Barthel}, title = {Zur isodiametrischen und isoperimetrischen {Ungleichung} in der {Relativgeometrie.}}, journal = {Commentarii mathematici Helvetici}, pages = {241--257}, publisher = {mathdoc}, volume = {33}, year = {1959}, zbl = {0091.35602}, url = {http://geodesic.mathdoc.fr/item/CMH_1959__33_139175/} }
Woldemar Barthel. Zur isodiametrischen und isoperimetrischen Ungleichung in der Relativgeometrie.. Commentarii mathematici Helvetici, Tome 33 (1959), pp. 241-257. http://geodesic.mathdoc.fr/item/CMH_1959__33_139175/