Cita APA (7a ed.)

Graf, B. (2001). Gems: The world's greatest treasures and their stories. Prestel.

Cita Chicago Style (17a ed.)

Graf, Bernhard. Gems: The World's Greatest Treasures and Their Stories. Munich: Prestel, 2001.

Cita MLA (9a ed.)

Graf, Bernhard. Gems: The World's Greatest Treasures and Their Stories. Prestel, 2001.