TY  - JOUR
AU  - A. I. Tret'yak
TI  - On~necessary conditions of arbitrary order for optimality in a~time-optimal problem
JO  - Sbornik. Mathematics
PY  - 1988
SP  - 255
EP  - 268
VL  - 60
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/SM_1988_60_1_a14/
LA  - en
ID  - SM_1988_60_1_a14
ER  -