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@article{MZM_1980_27_1_a7, author = {V. Kh. Sotirov}, title = {Nonfinitely approximable intuitionistic modal logics}, journal = {Matemati\v{c}eskie zametki}, pages = {89--94}, publisher = {mathdoc}, volume = {27}, number = {1}, year = {1980}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1980_27_1_a7/} }
V. Kh. Sotirov. Nonfinitely approximable intuitionistic modal logics. Matematičeskie zametki, Tome 27 (1980) no. 1, pp. 89-94. http://geodesic.mathdoc.fr/item/MZM_1980_27_1_a7/