@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/}
}