@article{MZM_1985_37_5_a0, author = {A. I. Budkin}, title = {Quasivarieties of groups having no coverings}, journal = {Matemati\v{c}eskie zametki}, pages = {609--616}, publisher = {mathdoc}, volume = {37}, number = {5}, year = {1985}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1985_37_5_a0/} }