@article{SM_1967_3_1_a5,
     author = {V. F. Gaposhkin},
     title = {A system of convergence},
     journal = {Sbornik. Mathematics},
     pages = {85--90},
     year = {1967},
     volume = {3},
     number = {1},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1967_3_1_a5/}
}