@article{AL_1981_20_4_a4,
     author = {R. K. Prank},
     title = {Expressibility in the elementary theory of recursively},
     journal = {Algebra i logika},
     pages = {427--439},
     year = {1981},
     volume = {20},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_1981_20_4_a4/}
}