Wei, D., Xiongkui, H. and Weimin, D. (2009) “Droplet size and spray pattern characteristics of PWM-based continuously variable spray”, International Journal of Agricultural and Biological Engineering, 2(1), pp. 8–18. Available at: https://ijabe.migration.pkpps06.publicknowledgeproject.org/index.php/ijabe/article/view/54 (Accessed: 27 February 2026).