Gao, Hong-Wen, and Peng-Fei Zhang. “Ananlysis of Nickel Chelate Solution With M-Chloroazo-Antipyrine and Determination of Trace Amounts of Nickel in Wastewater”. Asian Journal of Chemistry 11, no. 3 (March 30, 2010): 715–720. Accessed July 23, 2024. https://asianpubs.org/index.php/ajchem/article/view/23369.