@article{01433468, title = {Strong morphisms of groupoids.}, journal = {Balkan Journal of Geometry and its Applications (BJGA)}, volume = {4}, year = {1999}, pages = {91-102}, zbl = {0971.20034}, language = {en}, url = {http://dml.mathdoc.fr/item/01433468} }
Ivan, Gh. Strong morphisms of groupoids.. Balkan Journal of Geometry and its Applications (BJGA), Tome 4 (1999) pp. 91-102. http://gdmltest.u-ga.fr/item/01433468/