@article{DAN_1975_224_3_a1,
     author = {L. A. Biryukova},
     title = {On the $l$-completeness of functions with delays},
     journal = {Doklady Akademii Nauk},
     pages = {509--511},
     year = {1975},
     volume = {224},
     number = {3},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1975_224_3_a1/}
}