@misc{RM_1994_49_4_a3,
     title = {Joint sessions of the {Petrovskii} {Seminar} on {Differential} {Equations} and {Mathematical} {Problems} of {Physics} and of the {Moscow} {Mathematical} {Society} (sixteenth session,  {18--21~January~1994)}},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {79--143},
     publisher = {mathdoc},
     volume = {49},
     number = {4},
     year = {1994},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1994_49_4_a3/}
}