@article{AL_2015_54_5_a0,
     author = {P. E. Alaev},
     title = {Ash{\textquoteright}s theorem on $\Delta^0_\alpha$-categorical structures and a~condition for infinite $\Delta^0_\alpha$-dimension},
     journal = {Algebra i logika},
     pages = {551--574},
     publisher = {mathdoc},
     volume = {54},
     number = {5},
     year = {2015},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_2015_54_5_a0/}
}