Woo, Seung Min, et al. “Development of Seeder for Mixed Planting of Corn and Soybeans”. International Journal of Agricultural and Biological Engineering, vol. 10, no. 3, May 2017, pp. 95-101, https://www.ijabe.migration.pkpps06.publicknowledgeproject.org/index.php/ijabe/article/view/2543.