TY  - JOUR
AU  - V. P. Orevkov
TI  - Unsolvability in the modal predicate calculus of the class of formulas containing only one monadic predicate variable
JO  - Zapiski Nauchnykh Seminarov POMI
PY  - 1967
SP  - 168
EP  - 173
VL  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/ZNSL_1967_4_a16/
LA  - ru
ID  - ZNSL_1967_4_a16
ER  -