Md. Aminuddin, Rusdi, He Jifeng, and Rosni Abdullah. “Specifying Concurrent Controller of Production Cell Using the Notation of Shared State and Events of Duration Calculus”. Malaysian Journal of Computer Science 14, no. 2 (December 1, 2001): 81–94. Accessed May 18, 2024. https://ejournal.um.edu.my/index.php/MJCS/article/view/5865.