Gu, X., Zhang, Y., Chen, J. and Shen, L. 2014. Collision-free Multiple Unmanned Combat Aerial Vehicles Cooperative Trajectory Planning for Time-critical Missions using Differential Flatness Approach. Defence Science Journal. 64, 1 (Jan. 2014), 13-20. DOI:https://doi.org/10.14429/dsj.64.2999.