1. 1. http://en.wikipedia.org/wiki/Silver.
2. 2. Environmental Protection Agency (EPA), Ambient Water Quality Criteria for Silver, EPA 4405-80-071, Office of Water Regulations, Washington, D.C., 1980.
3. 3. Silver and Silver Compounds: Environmental Aspects, Concise International Chemical Assessment Document 44, International Programme on Chemical Safety, IPCS, (http://www.inchem.org/documents/cicads/cicads/cicad44.htm#3.02).
4. 4. E. Meian, “Metals and Their Compounds in the Environment”, 1991, VCH, New York.
5. 5. S. James Fritz, “Analytical Solid-Phase Extraction”, 1999, John Wiley & Sons Inc.