@article{VMUMM_1982_5_a14,
     author = {V. A. Skvortsov},
     title = {An example of a $U$-set for the {Walsh} system},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {53--55},
     year = {1982},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1982_5_a14/}
}