@article{SF_1992__44_1_135136,
     author = {J.S. Ponizovskii},
     title = {On a type of matrix semigroup.},
     journal = {Semigroup forum},
     pages = {125--128},
     year = {1992},
     volume = {44},
     number = {1},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SF_1992__44_1_135136/}
}