@article{DE_2005_41_1_a11,
     author = {V. A. Il'in and E. I. Moiseev},
     title = {Optimal boundary control of a string by an elastic force applied at one end, the other end being free},
     journal = {Differencialʹnye uravneni\^a},
     pages = {105--115},
     publisher = {mathdoc},
     volume = {41},
     number = {1},
     year = {2005},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_2005_41_1_a11/}
}