TY  - JOUR
AU  - V. P. Orevkov
TI  - Two unsolvable classes of formulas of classical predicate calculus
JO  - Zapiski Nauchnykh Seminarov POMI
PY  - 1968
SP  - 202
EP  - 210
VL  - 8
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/ZNSL_1968_8_a22/
LA  - ru
ID  - ZNSL_1968_8_a22
ER  -