@article{GDZPPN002184265,
title = {Note on the structure of a ruled surface.},
journal = {Journal f\"ur die reine und angewandte Mathematik},
volume = {238},
year = {1969},
pages = {68-73},
zbl = {0184.46802},
url = {http://dml.mathdoc.fr/item/GDZPPN002184265}
}
Maruyama, M.; Nagata, M. Note on the structure of a ruled surface.. Journal für die reine und angewandte Mathematik, Tome 238 (1969) pp. 68-73. http://gdmltest.u-ga.fr/item/GDZPPN002184265/