@article{GDZPPN002067609,
title = {Multiple fibres of a morphism.},
journal = {Commentarii mathematici Helvetici},
volume = {65},
year = {1990},
pages = {287-298},
zbl = {0714.14008},
url = {http://dml.mathdoc.fr/item/GDZPPN002067609}
}
Serrano, Fernando. Multiple fibres of a morphism.. Commentarii mathematici Helvetici, Tome 65 (1990) pp. 287-298. http://gdmltest.u-ga.fr/item/GDZPPN002067609/