Gemological Institute of America. Gems & gemology. Gemological Institute of America.
Chicago Style (17th ed.) CitationGemological Institute of America. Gems & Gemology. Los Angeles, Calif.: Gemological Institute of America.
MLA (9th ed.) CitationGemological Institute of America. Gems & Gemology. Gemological Institute of America.
Warning: These citations may not always be 100% accurate.