@article{GDZPPN002063980,
title = {Om multiple points of smooth immersions.},
journal = {Commentarii mathematici Helvetici},
volume = {55},
year = {1980},
pages = {521-527},
zbl = {0457.57013},
url = {http://dml.mathdoc.fr/item/GDZPPN002063980}
}
Ronga, Felice. Om multiple points of smooth immersions.. Commentarii mathematici Helvetici, Tome 55 (1980) pp. 521-527. http://gdmltest.u-ga.fr/item/GDZPPN002063980/