Voir la notice de l'article provenant de la source Math-Net.Ru
@article{MZM_1990_47_1_a1, author = {V. V. Arestov and V. P. Kondrat'ev}, title = {Certain extremal problem for nonnegative trigonometric polynomials}, journal = {Matemati\v{c}eskie zametki}, pages = {15--28}, publisher = {mathdoc}, volume = {47}, number = {1}, year = {1990}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1990_47_1_a1/} }
V. V. Arestov; V. P. Kondrat'ev. Certain extremal problem for nonnegative trigonometric polynomials. Matematičeskie zametki, Tome 47 (1990) no. 1, pp. 15-28. http://geodesic.mathdoc.fr/item/MZM_1990_47_1_a1/