@article{MM_1989_1_11_a12,
     author = {M. M. Lavrent'ev (Jn.)},
     title = {Estimations for solutions of an equation of mixed type},
     journal = {Matemati\v{c}eskoe modelirovanie},
     pages = {132--138},
     publisher = {mathdoc},
     volume = {1},
     number = {11},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MM_1989_1_11_a12/}
}