@article{00639840, title = {Transfer of the notion of }, journal = {Portugaliae Mathematica. Nova S\'erie}, volume = {51}, year = {1994}, pages = {13-23}, zbl = {0828.13010}, language = {en}, url = {http://dml.mathdoc.fr/item/00639840} }
Echi, Othman. Transfer of the notion of . Portugaliae Mathematica. Nova Série, Tome 51 (1994) pp. 13-23. http://gdmltest.u-ga.fr/item/00639840/