@article{MZ_1978__164_172774, author = {Jost-Hinrich Eschenburg}, title = {Trigonometrische {Charakterisierung} der {R\"aume} konstanter {Kr\"ummung.}}, journal = {Mathematische Zeitschrift}, pages = {143--152}, publisher = {mathdoc}, volume = {164}, year = {1978}, zbl = {0389.53005}, url = {http://geodesic.mathdoc.fr/item/MZ_1978__164_172774/} }