@article{1077469295, author = {Church, Philip T. and Hemmingsen, Erik}, title = {Light open maps on $n$ -manifolds}, journal = {Duke Math. J.}, volume = {27}, number = {1}, year = {1960}, pages = { 527-536}, language = {en}, url = {http://dml.mathdoc.fr/item/1077469295} }
Church, Philip T.; Hemmingsen, Erik. Light open maps on $n$ -manifolds. Duke Math. J., Tome 27 (1960) no. 1, pp. 527-536. http://gdmltest.u-ga.fr/item/1077469295/