1. Virta, R. L. Zeolites (natural). U.S. Geological Survey, Mineral Commodity Summaries. http://minerals.usgs.gov/minerals/pubs/commodity/zeolites/mcs-2011-zeoli.pdf (accessed 2011).
2. Application of natural zeolites in environmental remediation: A short review
3. SURFACTANT-MODIFIED NATURAL ZEOLITES FOR ENVIRONMENTAL APPLICATIONS IN WATER PURIFICATION
4. Natural Zeolites and Environment
5. Applications of Natural Zeolites in Pollution Abatement and Industry;Roque-Malherbe,2001