Article:
On Variational Integrators for Optimal Control of Mechanical Control Systems.
Authors:
L. Colombo-D.Martín de Diego-M.Zuccalli
Journal:
RACSAM- Rev. R. Acad. Cienc. Exactas Fis. Nat. Ser. A Mat.
URL:
http://www.springerlink.com/content/c4158266442378p4/