@article{TMF_1998_114_1_a0,
     author = {V. G. Danilov and V. P. Maslov and V. M. Shelkovich},
     title = {Algebras of the singularities of singular solutions to first-order quasi-linear strictly hyperbolic systems},
     journal = {Teoreti\v{c}eska\^a i matemati\v{c}eska\^a fizika},
     pages = {3--55},
     publisher = {mathdoc},
     volume = {114},
     number = {1},
     year = {1998},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TMF_1998_114_1_a0/}
}