A demonstration that Hilbert's projective metric, which has been shown to be applicable to a variety of problems involving linear mappings of a function space into itself, can also be applied to some nonlinear mappings which arise in dynamic programming.
Bellman, Richard Ernest and Thomas A. Brown, Projective Metrics in Dynamic Programming. Santa Monica, CA: RAND Corporation, 1965. https://www.rand.org/pubs/papers/P3060.html. Also available in print form.
Bellman, Richard Ernest and Thomas A. Brown, Projective Metrics in Dynamic Programming, Santa Monica, Calif.: RAND Corporation, P-3060, 1965. As of October 06, 2021: https://www.rand.org/pubs/papers/P3060.html