@article{JRAM_1971__246_151083,
     author = {Mireille P. Grillet},
     title = {On strongly strict extensions of semigroups.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {169--171},
     publisher = {mathdoc},
     volume = {246},
     year = {1971},
     zbl = {0211.33506},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1971__246_151083/}
}