1. Quasilinearization and Nonlinear Boundary-Value Problems;Bellman,1965
2. On the identification of systems and the unscrambling of data—I: Hidden periodicities;Bellman,1965
3. On the identification of systems and the unscrambling of data—II: An inverse problem in radiative transfer;Bellman,1965
4. Quasilinearization and the estimation of time-lags;Bellman;The RAND Corporation, RM-4990-NIH,1966