%0 Journal Article %A V. G. Timofeev %T N. P. Kuptsov’s method for the construction of an extremal function in an inequality between uniform norms of derivatives of functions on the half-line %J Trudy Instituta matematiki i mehaniki %D 2019 %P 220-239 %V 25 %N 2 %U http://geodesic.mathdoc.fr/item/TIMM_2019_25_2_a20/ %G ru %F TIMM_2019_25_2_a20