E.  Birgin ,   Y. G. Evtushenko ,   E. G. Birgin Automatic differentiation for optimal control problems. In "Dynamics of non-homogeneous systems" (Editor Yu. S. Popkov), Russian Academy of Sciences Institute for System Analysis , Vol 2, , p. 53-62 , 01.1999 E.  Birgin ,   Y. G. Evtushenko Automatic differentiation and spectral projected gradient methods for optimal control problems.. Optimization methods and software , Vol. 10, N 2 , p. 125-146 , 01.1998