@article{RM_1960_15_4_a6,
     author = {I. A. Vainshtein and M. A. Kreines},
     title = {Sequences of functions of the form $f(X(x)+Y(y))$},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     year = {1960},
     volume = {15},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/RM_1960_15_4_a6/}
}