@article{DAN_1996_351_5_a1,
     author = {P. A. Krutitskii},
     title = {On the asymptotics of the gradient of the solution and the appearance of singularities in an initial-boundary value problem for an equation of composite type},
     journal = {Doklady Akademii Nauk},
     pages = {586--591},
     publisher = {mathdoc},
     volume = {351},
     number = {5},
     year = {1996},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1996_351_5_a1/}
}