@article{1077468774, author = {Michael, E.}, title = {A theorem on semi-continuous set-valued functions}, journal = {Duke Math. J.}, volume = {26}, number = {1}, year = {1959}, pages = { 647-651}, language = {en}, url = {http://dml.mathdoc.fr/item/1077468774} }
Michael, E. A theorem on semi-continuous set-valued functions. Duke Math. J., Tome 26 (1959) no. 1, pp. 647-651. http://gdmltest.u-ga.fr/item/1077468774/