We present a simple method which simplifies the evaluation of the on-shell multiple box diagrams reducing them to triangle type ones. For the L-loop diagram one gets the expression in terms of Feynman parameters with 2L-fold integration. As examples we consider the 2 and 3 loops cases, the numerical integration up to six loops is also presented. The method is valid in six dimensions where neither UV not IR divergences appear.
@article{arxiv.1402.1024,
title = {Evaluation of Multi-Box Diagrams in Six Dimensions},
author = {D. I. Kazakov},
journal= {arXiv preprint arXiv:1402.1024},
year = {2015}
}