Mostaffa, Muhamad Faizal, et al. “E-SPAH: Aesthetic Innovation in UTHM’s Small-Scale Rainwater Harvesting System”. International Journal of Integrated Engineering, vol. 13, no. 5, Dec. 2021, pp. 239-46, https://penerbit.uthm.edu.my/ojs/index.php/ijie/article/view/9123.