Shengde, Chen, et al. “Effect of Wind Field below Unmanned Helicopter on Droplet Deposition Distribution of Aerial Spraying”. International Journal of Agricultural and Biological Engineering, vol. 10, no. 3, May 2017, pp. 67-77, https://ijabe.migration.pkpps06.publicknowledgeproject.org/index.php/ijabe/article/view/3078.