@article{ZNSL_1982_116_a8,
     author = {F. B. Koval'chik},
     title = {Some analogies of the {Hardy--Littlewood} equation},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {86--95},
     publisher = {mathdoc},
     volume = {116},
     year = {1982},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1982_116_a8/}
}