1. Teal Group Predicts Worldwide UAV Market Will Total $91 Billion in Its 2014 UAV Market Profile and Forecasthttp://www.tealgroup.com/index.php/about-teal-group-corporation/press-releases/ 118-2014-uav-press-release
2. Future of Unmanned Aviation;Valvanis,2015
3. Air Force ISR 2023: Delivering Decision Advantage;Otto,2013