@article{AL_2021_60_6_a6,
     author = {S. O. Speranski},
     title = {Modal bilattice logic and its extensions},
     journal = {Algebra i logika},
     pages = {612--635},
     year = {2021},
     volume = {60},
     number = {6},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_2021_60_6_a6/}
}