Grosjean, Carl. “On the Frequency Shift Resulting from the Perturbation of an Electromagnetic TM Wave-Mode by a Small Metallic Cylinder in a Resonant Cavity. Part 1: Detailed Theoretical Treatment”. Rev. Téc. Fac. Ing. Univ. Zulia 18, no. 1 (1). Accessed October 31, 2025. https://produccioncientifica.luz.edu.ve/index.php/tecnica/article/view/5466.