Xin, Zhe, et al. “Design and Optimization of a New Terrain-Adaptive Hitch Mechanism for Hilly Tractors”. International Journal of Agricultural and Biological Engineering, vol. 16, no. 4, Oct. 2023, pp. 134-4, https://ijabe.migration.pkpps06.publicknowledgeproject.org/index.php/ijabe/article/view/6992.