Wei, Zhang, et al. “Wind Tunnel Experimental Study on Droplet Drift Reduction by a Conical Electrostatic Nozzle for Pesticide Spraying”. International Journal of Agricultural and Biological Engineering, vol. 10, no. 3, May 2017, pp. 87-94, https://ijabe.migration.pkpps03.publicknowledgeproject.org/index.php/ijabe/article/view/3074.