TY  - JOUR
AU  - E.J. Wilczynski
TI  - A fundamental theorem in the theory of ruled surfaces
JO  - Mathematische Annalen
PY  - 1904
SP  - 249
EP  - 256
VL  - 58
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MAN_1904__58_158123/
ID  - MAN_1904__58_158123
ER  -