TY  - JOUR
AU  - S. V. Yablonskii
TI  - The structure of the upper neighborhood for predicate-describable classes in $P_k$
JO  - Doklady Akademii Nauk
PY  - 1974
SP  - 304
EP  - 307
VL  - 218
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1974_218_2_a14/
LA  - ru
ID  - DAN_1974_218_2_a14
ER  -