APA (7th ed.) Zitazioa

Kraus, E. H., & Slawson, C. B. (1947). Gems and gem materials (5a. ed.). McGraw-Hill.

Chicago Style (17th ed.) Zitazioa

Kraus, Edward Henry, eta Chester Baker Slawson. Gems and Gem Materials. 5a. ed. Nueva York: McGraw-Hill, 1947.

MLA (9th ed.) Zitazioa

Kraus, Edward Henry, eta Chester Baker Slawson. Gems and Gem Materials. 5a. ed. McGraw-Hill, 1947.