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@article{DE_1973_9_9_a7, author = {N. N. Petrov}, title = {The boundary of the set of controllability of plane holomorphic systems}, journal = {Differencialʹnye uravneni\^a}, pages = {1618--1626}, publisher = {mathdoc}, volume = {9}, number = {9}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1973_9_9_a7/} }
N. N. Petrov. The boundary of the set of controllability of plane holomorphic systems. Differencialʹnye uravneniâ, Tome 9 (1973) no. 9, pp. 1618-1626. http://geodesic.mathdoc.fr/item/DE_1973_9_9_a7/