@article{AL_2024_63_3_a1,
     author = {M. M. Arslanov and I. I. Batyrshin and M. M. Yamaleev},
     title = {$CEA$-operators and the {Ershov} hierarchy. {I}},
     journal = {Algebra i logika},
     pages = {248--270},
     publisher = {mathdoc},
     volume = {63},
     number = {3},
     year = {2024},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_2024_63_3_a1/}
}