Thair Sh. Mahmoud and  Tang Sai Hong and  Mohammed H. Marhaban,  Neuro Fuzzy and Self Tunging Fuzzy Controller to Improve Pitch and Yaw Control Systems Resposes of Twin Rotor MIMO System.   journal   = {International Journal of Mechanical and Mechatronics Engineering}, [online]. World Academy of Science, Engineering and Technology.
    February 2009, vol. 26(2). 165 - 169
    [viewed 26 January 2020]. Available from: https://publications.waset.org/pdf/8048.