@article{1077374793, author = {Church, P. T. and Hemmingsen, E.}, title = {Light open maps on $n$ -manifolds, III}, journal = {Duke Math. J.}, volume = {30}, number = {1}, year = {1963}, pages = { 379-389}, language = {en}, url = {http://dml.mathdoc.fr/item/1077374793} }
Church, P. T.; Hemmingsen, E. Light open maps on $n$ -manifolds, III. Duke Math. J., Tome 30 (1963) no. 1, pp. 379-389. http://gdmltest.u-ga.fr/item/1077374793/