%0 Journal Article %A V. A. Il'in %A E. I. Moiseev %T Optimal boundary control of a string by an elastic force applied at one end, the other end being free %J Differencialʹnye uravneniâ %D 2005 %P 105-115 %V 41 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_2005_41_1_a11/ %G ru %F DE_2005_41_1_a11