Schumann, W., Bradshaw, R., & Mills, K. (1993). Handbook of rocks, minerals, and gemstones. Boston: Houghton Mifflin Company.
Chicago Style CitationSchumann, Walter, R. Bradshaw, and K.A.G Mills. Handbook of Rocks, Minerals, and Gemstones. Boston: Houghton Mifflin Company, 1993.
MLA CitationSchumann, Walter, R. Bradshaw, and K.A.G Mills. Handbook of Rocks, Minerals, and Gemstones. Boston: Houghton Mifflin Company, 1993.
Warning: These citations may not always be 100% accurate.