@article{1183486350, author = {Levy, Harry}, title = {Normal congruences of curves in Riemann space}, journal = {Bull. Amer. Math. Soc.}, volume = {31}, number = {9-10}, year = {1925}, pages = { 39-42}, language = {en}, url = {http://dml.mathdoc.fr/item/1183486350} }
Levy, Harry. Normal congruences of curves in Riemann space. Bull. Amer. Math. Soc., Tome 31 (1925) no. 9-10, pp. 39-42. http://gdmltest.u-ga.fr/item/1183486350/