@misc{RM_1987_42_5_a20,
     title = {Sessions of the {Petrovskii} {Seminar} on differential equations and mathematical problems of physics},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     publisher = {mathdoc},
     volume = {42},
     number = {5},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/RM_1987_42_5_a20/}
}