TY  - JOUR
AU  - A. A. Shum
TI  - Varieties of algebraic systems and propositional calculi
JO  - Algebra i logika
PY  - 1984
SP  - 341
EP  - 359
VL  - 23
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/AL_1984_23_3_a7/
LA  - ru
ID  - AL_1984_23_3_a7
ER  -