1. NBR 10005: Leaching Tests;ABNT – Brazilian Association of Technical Standards,2004
2. NBR 10006: Solubilization Tests;ABNT – Brazilian Association of Technical Standards,2004
3. NBR 10004: Solid Waste – Classification;ABNT – Brazilian Association of Technical Standards,2004
4. A comparative analysis of gold-rich plant material using various analytical methods;Anderson;Microchem. J.,2005
5. Recent advances in the determination of (PGE) in exploration studies – a review;Balaram;J. Geol. Soc. India,2008