TY  - JOUR
AU  - Ya. I. Petrukhin
TI  - Natural deduction system for three-valued Heyting's logic
JO  - Vestnik Moskovskogo universiteta. Matematika, mehanika
PY  - 2017
SP  - 63
EP  - 66
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/VMUMM_2017_3_a9/
LA  - ru
ID  - VMUMM_2017_3_a9
ER  -