%0 Journal Article %A E. V. Romashevskaya %T Singular cases of the Darboux problem for a~system of equations of the type of the Tricomi equations %J Izvestiâ vysših učebnyh zavedenij. Matematika %D 1983 %P 73-75 %N 12 %I mathdoc %U http://geodesic.mathdoc.fr/item/IVM_1983_12_a15/ %G ru %F IVM_1983_12_a15