Nicholas Teo Yong Yeow, Tew Yiqi, Sing Hsia Yeoh, Yiauw Kah Haur, Lim Ming Jun, Ng Yik Heng, and Tan Hui Shan. 2022. “Robotic Delivery System for Multi-Storey Condominium Complexes”. Journal of Electronic Voltage and Application 3 (1): 1-15. https://penerbit.uthm.edu.my/ojs/index.php/jeva/article/view/10385.