: Ashok D. Dalvi; W. Gordon , Bacon & Robert C. Osborne (2004): "The Past and the Future of Nickel Laterites". Inco LimitedVer en PDFArquivado 27 de marzo de 2014 en Wayback Machine..
usgs.gov
minerals.usgs.gov
Lisa A. Corathers, Joseph Gambogi, Peter H. Kuck, John F. Papp, Désirée E. Polyak & Kim B. Shedd (2010). "2008 Minerals Yearbook - Ferroalloys"(PDF). United States Geological Survey.
web.archive.org
: Ashok D. Dalvi; W. Gordon , Bacon & Robert C. Osborne (2004): "The Past and the Future of Nickel Laterites". Inco LimitedVer en PDFArquivado 27 de marzo de 2014 en Wayback Machine..