Hsu, Der-jen, Chia-wei Lee, Wei-choung Tsai, and Yeh-chung Chien. “Essential and Toxic Metals in Animal Bone Broths”. Food & Nutrition Research 610 (July 18, 2017). Accessed December 4, 2021. https://foodandnutritionresearch.net/index.php/fnr/article/view/1245.