@article{DAN_1971_198_4_a6,
     author = {S. S. Marchenkov},
     title = {On semilattices of computable numerations},
     journal = {Doklady Akademii Nauk},
     pages = {766--768},
     year = {1971},
     volume = {198},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1971_198_4_a6/}
}