Mohd Syukri, Muhammad Afif Hakimie, et al. “Robust PID Performance for Temperature Regulation of Herb Drying System”. Evolution in Electrical and Electronic Engineering, vol. 4, no. 1, May 2023, pp. 705-14, https://penerbit.uthm.edu.my/periodicals/index.php/eeee/article/view/11418.