@article{CMH_1957__32_139148,
     author = {Gabriel Thierrin},
     title = {Contribution \`a la th\'eorie des anneaux et des demi-groupes.},
     journal = {Commentarii mathematici Helvetici},
     pages = {93--112},
     publisher = {mathdoc},
     volume = {32},
     year = {1957},
     zbl = {0079.24902},
     url = {http://geodesic.mathdoc.fr/item/CMH_1957__32_139148/}
}