@article{1214436221,
author = {Hebda, James J.},
title = {The regular focal locus},
journal = {J. Differential Geom.},
volume = {16},
number = {3},
year = {1981},
pages = { 421-429},
language = {en},
url = {http://dml.mathdoc.fr/item/1214436221}
}
Hebda, James J. The regular focal locus. J. Differential Geom., Tome 16 (1981) no. 3, pp. 421-429. http://gdmltest.u-ga.fr/item/1214436221/