1. R. Bellman and R. Kalaba,Quasilinearization and non-linear boundary-value problems, Elsevier, New York (1965).
2. L. Collatz,Numerical treatment of differential equations (Third edition), Springer, Berlin (1960).
3. L. Fox,Some improvements in the use of relaxation methods for the solution of ordinary and partial differential equations, Proc. Roy. Soc. A190 (1947), 31–59.
4. E. Hansen,On solving two-point boundary-value problems using interval arithmetic, (from Hansen (ed.)Topics in Interval Analysis), Clarendon Press, Oxford (1969).
5. E. Hansen,On linear algebraic equations with interval coefficients, (from Hansen (ed.)Topics in Interval Analysis), Clarendon Press, Oxford (1969).