@article{SD_1959-1960__13_1_A7_0,
     author = {Lefebvre, Pierre},
     title = {Sur les demi-groupes admettant pour image homomorphe un groupe avec z\'ero},
     journal = {S\'eminaire Albert Ch\^atelet et Paul Dubreil},
     note = {talk:7},
     pages = {1--18},
     year = {1959-1960},
     publisher = {Secr\'etariat math\'ematique},
     volume = {13},
     number = {1},
     zbl = {0125.28503},
     language = {fr},
     url = {https://www.numdam.org/item/SD_1959-1960__13_1_A7_0/}
}