@article{MZM_2006_80_6_a11,
     author = {V. I. Ivanov},
     title = {On the {Tur\'an} and {Delsarte} problems for periodic positive definite functions},
     journal = {Matemati\v{c}eskie zametki},
     pages = {934--939},
     publisher = {mathdoc},
     volume = {80},
     number = {6},
     year = {2006},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2006_80_6_a11/}
}