TY  - JOUR
AU  - Figallo, Aldo V.
TI  - On the congruences in four-valued modal algebras
JO  - Portugaliae mathematica
PY  - 1992
SP  - 249
EP  - 261
VL  - 49
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/PORMA_1992__49_2_115790/
LA  - en
ID  - PORMA_1992__49_2_115790
ER  -