Extraction of copper and zinc from naturally contaminated copper mine soils: chemical fractionation analysis and risk assessment

- Xiao, Jiu-Hua; Zhou, Jun; Wang, Zhao-hui; Li, Si-Yue; Zhang, Wei-chao; Fang, Chang-ling; Guo, Yao-guang; Xiao, Dong-xue; Lou, Xiao-yi; Liu, Jian-she