Voir la notice de l'article provenant de la source Novi sad journal of mathematics website
@article{NSJOM_1984__14__a17, author = {Bogdanovi\'c Stojan}, title = {$\sigma$-inverse semigroups}, journal = {Novi Sad Journal of Mathematics}, pages = {197-200}, publisher = {mathdoc}, volume = {14}, year = {1984}, url = {http://geodesic.mathdoc.fr/item/NSJOM_1984__14__a17/} }
Bogdanović Stojan. $\sigma$-inverse semigroups. Novi Sad Journal of Mathematics, Tome 14 (1984). http://geodesic.mathdoc.fr/item/NSJOM_1984__14__a17/