Enclosure of solutions of weakly nonlinear elliptic boundary value problems and their computation. - Rudolf L. Voller (Computing, 1989)

A monotone including multigrid-method. - Rudolf L. Voller (Computing, 1990)

What can interval analysis do for global optimization? - Helmut Ratschek; Rudolf L. Voller (J. Glob. Optim., 1991)