Sumarsono, F. A. N. Farida Afiatna, and N. Muflihah, “The Monitoring System of Soil PH Factor Using IoT-Webserver-Android and Machine Learning: A Case Study”, Int. J. Adv. Sci. Eng. Inf. Technol., vol. 14, no. 1, pp. 118–130, Feb. 2024.