@article{ZNSL_2021_506_a4,
     author = {A. F. Vakulenko},
     title = {On expansions over harmonic polynomial products in~${\mathbb R}^3$},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {36--42},
     publisher = {mathdoc},
     volume = {506},
     year = {2021},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2021_506_a4/}
}