1. Primatesta S, Rizzo A, la Cour-Harbo A (2020) Ground risk map for UAVs in urban environments. J Intell Rob Syst 97:489–509
2. Bowden M (2013) How the predator drone changed the character of war. Smithsonian Magazine, Nov 2013. https://www.smithsonianmag.com/history/how-the-predator-drone-changed-the-character-of-war-3794671/
3. Zhao L, Research on operational rules of US UAV close air support. Ship Electron Eng 40(1)
4. Rempfer K (2019) Air force offers glimpse of new, stealthy combat drone during first flight, 8 Mar 2019. https://www.airforcetimes.com/news/your-air-force/2019/03/08/air-force-offers-glimpse-of-new-stealthy-combat-drone-during-first-flight/
5. Task Force Co-chairs, Gen. Abizaid JP (US Army, Ret.) (2015) Recommendations and report of the task force on US drone policy, 2nd ed. The Stimson Center