TY  - JOUR
AU  - A. U. Muravitskii
TI  - Finite approximability of the~$I^\Delta$ calculus and the existence of an extension having no model
JO  - Matematičeskie zametki
PY  - 1981
SP  - 907
EP  - 916
VL  - 29
IS  - 6
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MZM_1981_29_6_a11/
LA  - ru
ID  - MZM_1981_29_6_a11
ER  -