@article{1256054563, author = {Ganea, T.}, title = {Lusternik-Schnirelmann category and strong category}, journal = {Illinois J. Math.}, volume = {11}, number = {4}, year = {1967}, pages = { 417-427}, language = {en}, url = {http://dml.mathdoc.fr/item/1256054563} }
Ganea, T. Lusternik-Schnirelmann category and strong category. Illinois J. Math., Tome 11 (1967) no. 4, pp. 417-427. http://gdmltest.u-ga.fr/item/1256054563/