@article{MZM_1980_28_3_a9,
     author = {A. P. Beltiukov},
     title = {Hierarchy of complexity of computation of partial functions with values~0 and~1},
     journal = {Matemati\v{c}eskie zametki},
     pages = {423--431},
     publisher = {mathdoc},
     volume = {28},
     number = {3},
     year = {1980},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1980_28_3_a9/}
}