TY  - JOUR
AU  - V. V. Rybakov
TI  - A criterion for admissibility of inference rules in modal and
JO  - Doklady Akademii Nauk
PY  - 1985
SP  - 538
EP  - 541
VL  - 284
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1985_284_3_a5/
LA  - ru
ID  - DAN_1985_284_3_a5
ER  -