Zhang, Ganghong, Wanlin Gao, Sha Tao, Lina Yu, Guofeng Zhang, and Xuan Luo. “Online Ultrasonic Terminal for Measuring Pig Backfat Thickness”. International Journal of Agricultural and Biological Engineering 11, no. 2 (March 31, 2018): 190–195. Accessed January 27, 2026. https://ijabe.org/index.php/ijabe/article/view/3278.