Nonlinear Perturbations of Uncoupled Systems of Elliptic Operators. R.H. jr. Martin — 1974 Mathematische Annalen
Reaction-diffusion systems with time delays: monotonicity, invariance, comparison and convergence. R.H. jr. Martin; H.L. Smith — 1991 Journal für die reine und angewandte Mathematik
Projection Seminorms and the Field of Values of Linear Operators. R.H. jr. Martin; J.H. III. Lightbourne — 1975 Numerische Mathematik