1. Rybakov M., Shkatov D. Algorithmic properties of first-order modal logics of finite Kripke frames in restricted languages // Journal of Logic and Computation. 2020. V.30. Issue 7. P.1305-1329.
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2. Rybakov M., Shkatov D. Complexity of finite-variable fragments of products with non-transitive modal logics // Journal of Logic and Computation. 2022. V.32. Issue 5. P.853-870.
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