On the evaluation of three--loop scalar integrals in the massive case

I describe a method to calculate a class of three-loop selfenergy diagrams for arbitrary internal masses and external momentum. This method combines analytical results and numerical integration, and is suitable for implementation in a computer program to produce fast and accurate results. For the class of Feynman diagrams considered in this paper this method leads to a two-fold integral which needs to be evaluated numerically. Results are given for a range of masses and external momentum.