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On Belnapian modal algebras: Representations, homomorphisms, congruences, and so on
Siberian Electronic Mathematical Reports. 2013. Vol. 10. P. 517–534.
We obtain a bunch of principal results on Belnapian modal algebras (henceforth called BK-lattices) — these results may serve as a semantical basis for further investigation of the lattice of extensions of Belnapian modal logic (denoted by BK here).