@article{IM2_2003_67_2_a7,
     author = {V. I. Khomich},
     title = {The simple substitution property for superintuitionistic propositional logics and its relation to the separability property},
     journal = {Izvestiya. Mathematics},
     pages = {377--404},
     year = {2003},
     volume = {67},
     number = {2},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_2003_67_2_a7/}
}