Calculating Gaussian integrals in Quantum Field Theory (QFT) often involves five specific integrals, with a focus on the last one and differentiation under the integration sign for the first four. The discussion highlights the importance of understanding four-momentum, denoted as 'q', in these calculations. A reference to Zee's "QFT in a Nutshell" is suggested, as it contains valuable derivations relevant to these integrals. Additionally, the possibility of accessing the book on Amazon for further insights is mentioned. Mastery of these integrals is crucial for accurate QFT calculations.