TY  - JOUR
AU  - V. V. Rybakov
TI  - A criterion for admissibility of rules in the modal system
JO  - Algebra i logika
PY  - 1984
SP  - 546
EP  - 572
VL  - 23
IS  - 5
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/AL_1984_23_5_a5/
LA  - ru
ID  - AL_1984_23_5_a5
ER  -