TY  - JOUR
AU  - E. I. Zheleznov
TI  - Necessary optimality conditions for singular extremals
JO  - Differencialʹnye uravneniâ
PY  - 1975
SP  - 749
EP  - 752
VL  - 11
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1975_11_4_a18/
LA  - ru
ID  - DE_1975_11_4_a18
ER  -