samsuni muhamad husni bin samsuni, Shaari MF. Development of Vending Machine Operation System Using Programmable Logic Controller (PLC). peat [Internet]. 2021 Jun. 22 [cited 2024 Aug. 17];2(1):930-6. Available from: https://penerbit.uthm.edu.my/periodicals/index.php/peat/article/view/979