Vybornov, A., A. Trofimov, S. Pashhenko, A. Krylov, A. Shishkin, and O. De-Monderik. “Enhancement of RF Field Stability in an LLRF System via Inclusion of a Second-Order Integral Term in the PID Controller Transfer Function”. Informatics and Automation, Vol. 25, no. 4, July 2026, pp. 1283-06, DOI:10.15622/ia.25.4.11.