Marso, Karol, and Dominik Macko. “A New Parking-Space Detection System Using Prototyping Devices and Bluetooth Low Energy Communication”. International Journal of Engineering and Technology Innovation 9, no. 2 (April 1, 2019): 108-118. Accessed April 18, 2021. https://ojs.imeti.org/index.php/IJETI/article/view/1624.