Abo Mosali, Najmaddin, and Syariful Syafiq Shamsudin. “Issues of Designing a Model Adaptive Controller Without a State Observer”. Progress in Aerospace and Aviation Technology, vol. 1, no. 1, Dec. 2021, pp. 1-6, https://publisher.uthm.edu.my/ojs/index.php/paat/article/view/10383.