2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/227011Feynman diagrams may be evaluated by Mellin-Barnes representations of their Feynman parameter integrals in d=4-2\eps dimensions. Recently, the Mathematica toolkit AMBRE has been developed for the automatic derivation of such representations with a loop-by-loop approach. We describe the package and exemplify its use with the \eps-expansion of the massive one-loop QED vertex function.10 pages, contribution to proceedings of ACAT, Amsterdam, The Netherlands, April 23-27, 2007, several (trivial) typos correctedHigh Energy Physics - Phenomenologytext