@article{IVM_1969_12_a13,
     author = {T. V. \v{C}ekmarev},
     title = {Cauchy, {Goursat,} and {Cauchy--Goursat} problems for degenerating systems of {equations.~I}},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {99--111},
     publisher = {mathdoc},
     number = {12},
     year = {1969},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1969_12_a13/}
}