@article{MZM_1980_27_6_a4,
     author = {S. S. Marchenkov},
     title = {Existence of superposition bases in countable primitive-recursively closed classes of one-place functions},
     journal = {Matemati\v{c}eskie zametki},
     pages = {877--883},
     publisher = {mathdoc},
     volume = {27},
     number = {6},
     year = {1980},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1980_27_6_a4/}
}