Sheila C. Wang, Yanjie Li, ManYing Ho, Maria-Elena Bernal, Andrew M. Sydor, Wasim R. Kagzi, Deborah B. Zamble,
The response of Escherichia coli NikR to nickel: a second nickel-binding site. Biochemistry. ,vol. 49, pp. 6635- 6645 ,(2010) ,
10.1021/BI100685K