Akaiso Etim, Ushie James Ogri, Donatus Enang Bassey Okwong,. “DESIGN AND CONSTRUCTION OF DOOR LOCKING SECURITY SYSTEM USING GSM”. International Journal of Engineering and Computer Science 2, no. 7 (July 30, 2013). Accessed May 19, 2024. http://ijecs.in/index.php/ijecs/article/view/1674.