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@article{MZM_1967_1_6_a11, author = {V. G. Boltyanskii}, title = {Non-oscillatory optimal systems of the second order}, journal = {Matemati\v{c}eskie zametki}, pages = {703--714}, publisher = {mathdoc}, volume = {1}, number = {6}, year = {1967}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1967_1_6_a11/} }
V. G. Boltyanskii. Non-oscillatory optimal systems of the second order. Matematičeskie zametki, Tome 1 (1967) no. 6, pp. 703-714. http://geodesic.mathdoc.fr/item/MZM_1967_1_6_a11/