TY  - JOUR
AU  - A. U. Muravitskii
TI  - Extensions of the provability logic
JO  - Matematičeskie zametki
PY  - 1983
SP  - 915
EP  - 927
VL  - 33
IS  - 6
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MZM_1983_33_6_a12/
LA  - ru
ID  - MZM_1983_33_6_a12
ER  -