Zeng, Shan, et al. “Structural Design and Parameter Determination for Fluted-Roller Fertilizer Applicator”. International Journal of Agricultural and Biological Engineering, vol. 13, no. 2, Apr. 2020, pp. 101-10, https://ijabe.migration.pkpps03.publicknowledgeproject.org/index.php/ijabe/article/view/4999.