@article{MZM_2017_101_2_a6,
     author = {V. P. Zastavnyi},
     title = {Positive {Definiteness} of a {Family} of {Functions}},
     journal = {Matemati\v{c}eskie zametki},
     pages = {215--225},
     publisher = {mathdoc},
     volume = {101},
     number = {2},
     year = {2017},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2017_101_2_a6/}
}