%0 Journal Article
%A V. I. Berdyshev
%T Characterization of optimal trajectories in $\mathbb {R}^3$
%J Trudy Instituta matematiki i mehaniki
%D 2018
%P 40-45
%V 24
%N 2
%U http://geodesic.mathdoc.fr/item/TIMM_2018_24_2_a4/
%G ru
%F TIMM_2018_24_2_a4