@article{SM_2001_192_5_a5,
     author = {D. A. Khrychev},
     title = {Optimal programmed controls: existence and approximation},
     journal = {Sbornik. Mathematics},
     pages = {763--783},
     publisher = {mathdoc},
     volume = {192},
     number = {5},
     year = {2001},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_2001_192_5_a5/}
}