@misc{RM_1988_43_4_a33,
     title = {Joint sessions of the {Petrovskii} {Seminar} on differential equations and mathematical problems of physics and of the {Moscow} {Mathematical} {Society} (eleventh session, {18--21~January~1988)}},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     publisher = {mathdoc},
     volume = {43},
     number = {4},
     year = {1988},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/RM_1988_43_4_a33/}
}