Zhang, Chun-Jiang, Wen-Hua Chen, Yan Zhao, and Xiao-Ling Qiao. 2012. “Determination of Seven Kinds of Trace Elements in Different Organs of Beijing Black Pig”. Asian Journal of Chemistry 24 (9):3931-32. https://asianpubs.org/index.php/ajchem/article/view/9503.