@article{GDZPPN002023520, title = {Nearly Spherical Surfaces. (Short Communication).}, journal = {Aequationes mathematicae}, volume = {2}, year = {1969}, pages = {200-200}, zbl = {0177.49501}, url = {http://dml.mathdoc.fr/item/GDZPPN002023520} }
Guggenheimer, H. Nearly Spherical Surfaces. (Short Communication).. Aequationes mathematicae, Tome 2 (1969) p. 200. http://gdmltest.u-ga.fr/item/GDZPPN002023520/