1. Stability Theory of Differential Equations;Bellman,1969
2. Methods of Nonlinear Analysis;Bellman,1969
3. Perturbation Techniques in Mathematics, Physics and Engineering;Bellman,1964
4. Relative invariants, closure, and stochastic differential equations;Bellman;J. Math. Anal. Appl.,1966
5. The iteration of power series in two variables;Bellman;Duke Math. J.,1952