@article{DE_1976_12_12_a20,
     author = {V. A. Srochko},
     title = {On the optimality of singular controls in systems with after-effect},
     journal = {Differencialʹnye uravneni\^a},
     pages = {2275--2278},
     publisher = {mathdoc},
     volume = {12},
     number = {12},
     year = {1976},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1976_12_12_a20/}
}