1. Doole, M., Ellerbroek, J. and Hoekstra, J. (2018). Drone delivery: urban airspace traffic density estimation. Eighth SESAR Innovation Days, 8 p.
2. Haddad, C., Chaniotakis, E., Straubinger, A., Plötner, K. and Antoniou, C. (2020). Factors affecting the adoption and use of urban air mobility. Transportation Research Part A: Policy and Practice, vol. 132, pp. 696–712. DOI: 10.1016/j.tra.2019.12.020
3. PytlikZillig, L.M., Walther, J.C., Detweiler, C., Elbaum, S. and Houston, A. (2020). Public opinions of unmanned aerial technologies in 2014-2019: a technical and descriptive report. University of Nebraska Public Policy Center, Lincoln. Available at: https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1000&context=lpz (accessed 10.11.2020).
4. Cohn, P., Green, A., Langstaff, M. and Roller, M. (2017). Commercial drones are here: the future of unmanned aerial systems. McKinsey&Company. Available at: https://www.mckinsey.com/industries/travel-logistics-and-infrastructure/our-insights/commercialdrones-are-here-the-future-of-unmanned-aerial-systems (accessed 10.11.2020).
5. Sandvik, K.B. (2015). African drone stories. BEHEMOTH – A Journal on Civilisation, vol. 8, no. 2, pp. 73–96. DOI: 10.6094/behemoth.2015.8.2.870