@article{MM_1990_2_1_a8,
     author = {A. V. Sarychev and A. L. Shuvalov},
     title = {The stability of the acoustic axes in elastic media},
     journal = {Matemati\v{c}eskoe modelirovanie},
     pages = {105--111},
     publisher = {mathdoc},
     volume = {2},
     number = {1},
     year = {1990},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MM_1990_2_1_a8/}
}