@article{IVM_1972_12_a4,
     author = {L. M. Gluskin and I. L. Perepelitsyn},
     title = {Normal extensions of semi-groups},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {46--54},
     publisher = {mathdoc},
     number = {12},
     year = {1972},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1972_12_a4/}
}