@article{DAN_1969_186_5_a3,
     author = {A. Dzhuraev},
     title = {Boundary value problems for systems of second order equations of composite type which have one multiple family of real characteristics},
     journal = {Doklady Akademii Nauk},
     pages = {1002--1005},
     publisher = {mathdoc},
     volume = {186},
     number = {5},
     year = {1969},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1969_186_5_a3/}
}