@article{AL_2019_58_6_a1,
     author = {Yu. L. Ershov},
     title = {The $d$-rank of an $\alpha$-space does not exceed~$1$},
     journal = {Algebra i logika},
     pages = {706--713},
     publisher = {mathdoc},
     volume = {58},
     number = {6},
     year = {2019},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_2019_58_6_a1/}
}