@article{SM_1986_55_2_a0,
     author = {V. V. Kucherenko and L. Yu. Motylev},
     title = {A~parametrix for a~nonstrictly hyperbolic equation with nonsmooth characteristics},
     journal = {Sbornik. Mathematics},
     pages = {287--307},
     publisher = {mathdoc},
     volume = {55},
     number = {2},
     year = {1986},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1986_55_2_a0/}
}