TY  - RPRT
TI  - An approach to sub-optimal feedback control of non-linear systems.
AU  - Clark, L. G.
AU  - Garrard, W. L.
AU  - Mcclamroch, N. H.
PY  - 1967
UR  - https://ntrs.nasa.gov/citations/19670061916
ID  - 19670061916
ER  -