%0 Journal Article %A S. O. Speranski %T Modal bilattice logic and its extensions %J Algebra i logika %D 2021 %P 612-635 %V 60 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/AL_2021_60_6_a6/ %G ru %F AL_2021_60_6_a6