@article{SJVM_2002_5_1_a6,
     author = {G. I. Shishkin},
     title = {Grid approximations with an improved rate of convergence for singularly perturbed elliptic equations in domains with characteristic boundaries},
     journal = {Sibirskij \v{z}urnal vy\v{c}islitelʹnoj matematiki},
     pages = {71--92},
     publisher = {mathdoc},
     volume = {5},
     number = {1},
     year = {2002},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/SJVM_2002_5_1_a6/}
}