Chính (2021) “SURVEY RESULTS ON THE VERTICAL LANDING AERODYNAMIC CHARACTERISTICS OF THREE JOINTS HELICOPTER ROTOR AND DETERMINES THE VORTEX RING STATE”, Journal of Military Science and Technology, (72), pp. 3–9. Available at: https://online.jmst.info/index.php/jmst/article/view/73 (Accessed: 5 May 2024).