@article{DAN_1957_117_5_a7,
     author = {V. P. Mikhailov},
     title = {Non-analytical solutions of {Goursat's} problem for a system of differential equations in two independent variables},
     journal = {Doklady Akademii Nauk},
     pages = {759--762},
     publisher = {mathdoc},
     volume = {117},
     number = {5},
     year = {1957},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1957_117_5_a7/}
}