1. Singular perturbation method for reducing the model order in optimal control design;Kokotović;IEEE Trans. Aut. Control,1968
2. Singular Perturbations of a Class of Two Point Boundary Value Problems Arising in Optimal Control;Hadlock,1970
3. The singularly perturbed linear state regulator problem;O'Malley;SIAM J. Control,1972
4. On the Asymptotic Solution of Certain Nonlinear Singularly Perturbed Optimal Control Problems;O'Malley,1972
5. Asymptotic Expansions of Singularly Perturbed Quasi-linear Optimal Systems;Sannuti,1971