2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/100783Partition- and moment functions for a general (not necessarily Gaussian) functional measure that is perturbed by a Gibbs factor are calculated using generalized Feynman graphs. From the graphical calculus, a new notion of Wick ordering arises, that coincides with orthogonal decompositions of Wiener-Itô type only if the measure is Gaussian. Proving a generalized linked cluster theorem, we show that the logarithm of the partition function can be expanded in terms of connected Feynman graphs ("linked cluster theorem").14 pages, 6 figures, further typos fixed, more details added on graph theoretic notions using the theory of speciesMathematical Physics81T18, 82B28text