APA Citation

Hurlbut, C. S., & Kammerling, R. C. (1993). Gemología (2a. ed.). Barcelona: Omega.

Chicago Style Citation

Hurlbut, Cornelius S., and Robert C. Kammerling. Gemología. 2a. ed. Barcelona: Omega, 1993.

MLA Citation

Hurlbut, Cornelius S., and Robert C. Kammerling. Gemología. 2a. ed. Barcelona: Omega, 1993.

Warning: These citations may not always be 100% accurate.