@article{IVM_1961_1_a10,
     author = {I. S. Kukles and A. M. Suyarshaev},
     title = {On quasi-singular characteristic orders of smallness},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {104--118},
     year = {1961},
     number = {1},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1961_1_a10/}
}