Abdalla, M. O., and S. Al-Baradie. “Real Time Optimal Tuning of Quadcopter Attitude Controller Using Particle Swarm Optimization”. Journal of Engineering and Technological Sciences, vol. 52, no. 5, Sept. 2020, pp. 745-64, doi:10.5614/j.eng.technol.sci.2020.52.5.10.