Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{CMH_1931__3_138559, author = {Lars Ahlfors}, title = {Zur {Bestimmung} des {Typus} einer {Riemannschen} {Fl\"ache.}}, journal = {Commentarii mathematici Helvetici}, pages = {173--178}, publisher = {mathdoc}, volume = {3}, year = {1931}, zbl = {57.0370.03}, url = {http://geodesic.mathdoc.fr/item/CMH_1931__3_138559/} }
Lars Ahlfors. Zur Bestimmung des Typus einer Riemannschen Fläche.. Commentarii mathematici Helvetici, Tome 3 (1931), pp. 173-178. http://geodesic.mathdoc.fr/item/CMH_1931__3_138559/