1. Health guide: safe use of nickel in the workplace, 3rd ed. Toronto: Nickel Institute; 2008.
2. International programme on chemical safety, environmental health criteria 108, Nickel, WHO, Geneva, Switzerland; 1991.
3. Air quality guidelines for Europe 2000. Full background material to WHO Regional publications, European Series No. 91 [CD-ROM]. Copenhagen, Denmark: WHO Regional Office for Europe; 2001.[chapter 6.10 (Nickel), Table 1].
4. Sperling M. EVISA link database: all about nickel. European Virtual Institute for Speciation Analysis (EVISA); 2012, http://www.speciation.net/Database/Links/all-about-nickel.html.