@article{GDZPPN00238003X, title = {Differentialgeometrie des isotropen Raumes. III Fl\"achentheorie}, journal = {Mathematische Zeitschrift}, volume = {48}, year = {1942}, pages = {369-427}, zbl = {68.0440.01}, url = {http://dml.mathdoc.fr/item/GDZPPN00238003X} }
Strubecker, K. Differentialgeometrie des isotropen Raumes. III Flächentheorie. Mathematische Zeitschrift, Tome 48 (1942) pp. 369-427. http://gdmltest.u-ga.fr/item/GDZPPN00238003X/