Shamseldin, M. A., M. Sallam, A. M. Bassiuny, and A. M. Abdel Ghany. “Real-Time Implementation of an Enhanced Nonlinear PID Controller Based on Harmony Search for One-Stage Servomechanism System”. Journal of Mechanical Engineering and Sciences, vol. 12, no. 4, Dec. 2018, pp. 4161-79, doi:10.15282/jmes.12.4.2018.13.0359.