@article{IVM_2017_8_a4,
     author = {R. M. Safina},
     title = {Keldysh problem for mixed type equation with strong characteristic degeneration and singular coefficient},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {53--61},
     publisher = {mathdoc},
     number = {8},
     year = {2017},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_2017_8_a4/}
}