@article{ZNSL_2021_502_a4,
     author = {N. V. Proskurin},
     title = {On exponential sums and flowers},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {133--138},
     publisher = {mathdoc},
     volume = {502},
     year = {2021},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_2021_502_a4/}
}