TY  - JOUR
AU  - V. I. Amstislavskii
TI  - On recursive characterizations of sets obtainable by means of $R^c$-operations
JO  - Doklady Akademii Nauk
PY  - 1975
SP  - 257
EP  - 260
VL  - 224
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1975_224_2_a0/
LA  - ru
ID  - DAN_1975_224_2_a0
ER  -