Xue, Bai, Li Zifu, Wang Xuemei, He Xi, Cheng Shikun, Bai Xiaofeng, and Gao Ruiling. “Online Measurement of Alkalinity in Anaerobic Co-Digestion Using Linear Regression Method”. International Journal of Agricultural and Biological Engineering 10, no. 1 (January 23, 2017): 176–183. Accessed December 26, 2025. https://ijabe.migration.pkpps03.publicknowledgeproject.org/index.php/ijabe/article/view/2701.