Voir la notice de l'article provenant de la source Mathematicac Balkanica website
@article{MABA_1988_2_3-4_a2, author = {B. Wegner}, title = {A {Differential} {Geometric} {Proof} of the {Local} {Geometric} {Characterization} of {Spheres} and {Cylinders} by {Boas}}, journal = {Mathematica balkanica}, pages = {294}, publisher = {mathdoc}, volume = {2}, number = {3-4}, year = {1988}, url = {http://geodesic.mathdoc.fr/item/MABA_1988_2_3-4_a2/} }
B. Wegner. A Differential Geometric Proof of the Local Geometric Characterization of Spheres and Cylinders by Boas. Mathematica balkanica, Tome 2 (1988) no. 3-4, p. 294. http://geodesic.mathdoc.fr/item/MABA_1988_2_3-4_a2/