@article{CTGDC_1966__8__A1_0, author = {Ehresmann, Charles}, title = {Trends toward unity in mathematics}, journal = {Cahiers de Topologie et G\'eom\'etrie Diff\'erentielle Cat\'egoriques}, volume = {8}, year = {1966}, pages = {1-7}, zbl = {0147.24103}, language = {en}, url = {http://dml.mathdoc.fr/item/CTGDC_1966__8__A1_0} }
Ehresmann, Charles. Trends toward unity in mathematics. Cahiers de Topologie et Géométrie Différentielle Catégoriques, Tome 8 (1966) pp. 1-7. http://gdmltest.u-ga.fr/item/CTGDC_1966__8__A1_0/