@article{TRSPY_1989_186_a4,
     author = {V. N. Shchelkachev},
     title = {Singularities of mathematical solutions of problems connected with the investigation of one-dimensional flows in multidimensional spaces},
     journal = {Informatics and Automation},
     pages = {19--26},
     publisher = {mathdoc},
     volume = {186},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TRSPY_1989_186_a4/}
}