Tsay, Lok Wai Jacky, et al. “Static and Dynamic Evaluations of Acoustic Positioning System Using TDMA and FDMA for Robots Operating in a Greenhouse”. International Journal of Agricultural and Biological Engineering, vol. 15, no. 5, Nov. 2022, pp. 28-33, https://ijabe.migration.pkpps03.publicknowledgeproject.org/index.php/ijabe/article/view/6796.