@article{CTGDC_2008__49_2_142_0, author = {Ehresmann, Andr\'ee}, title = {Fifty years of research}, journal = {Cahiers de Topologie et G\'eom\'etrie Diff\'erentielle Cat\'egoriques}, volume = {49}, year = {2008}, pages = {142-152}, mrnumber = {2426400}, zbl = {1147.01320}, language = {en}, url = {http://dml.mathdoc.fr/item/CTGDC_2008__49_2_142_0} }
Ehresmann, Andrée C. Fifty years of research. Cahiers de Topologie et Géométrie Différentielle Catégoriques, Tome 49 (2008) pp. 142-152. http://gdmltest.u-ga.fr/item/CTGDC_2008__49_2_142_0/