PEI, Xiaoshuai; MENG, Chao; LI, Minzan; YANG, Wei; ZHOU, Peng. Measurement of soil electrical conductivity based on direct digital synthesizer (DDS) and digital oscilloscope. International Journal of Agricultural and Biological Engineering, Beijing, China, v. 12, n. 6, p. 162–168, 2019. Disponível em: https://www.ijabe.org/index.php/ijabe/article/view/4840. Acesso em: 1 feb. 2026.