1. A Suprasystem of Probability Distributions
2. Voit, E. O. and Rust, P. F. Noncentral chi-square distributions computed by S-system differential equations. Proceedings of the Statistical Computing Section, ASA. pp.118–121.
3. Voit, E. O. and Rust, P. F. S-system computation of central and noncentralFdensities and cumulatives. Proceedings of the Statistical Computing Section, ASA. pp.274–279.