@article{MZM_1987_42_3_a4,
     author = {I. E. Egorov},
     title = {First boundary problem for a nonclassical equation},
     journal = {Matemati\v{c}eskie zametki},
     pages = {394--402},
     publisher = {mathdoc},
     volume = {42},
     number = {3},
     year = {1987},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1987_42_3_a4/}
}