@article{CTGDC_1967__9_2_243_0, author = {Hilton, Peter}, title = {Filtrations}, journal = {Cahiers de topologie et g\'eom\'etrie diff\'erentielle}, pages = {243--253}, publisher = {Dunod \'editeur, publi\'e avec le concours du CNRS}, volume = {9}, number = {2}, year = {1967}, mrnumber = {228562}, zbl = {0204.03003}, language = {en}, url = {http://www.numdam.org/item/CTGDC_1967__9_2_243_0/} }