APA (7th ed.) Citation

Harris, J., De Bellaigue, G., & Millar, O. (1968). Buckingham Palace and its treasures. Viking Press.

Chicago Style (17th ed.) Citation

Harris, John, Geoffrey De Bellaigue, and Oliver Millar. Buckingham Palace and Its Treasures. New York: Viking Press, 1968.

MLA (8th ed.) Citation

Harris, John, et al. Buckingham Palace and Its Treasures. Viking Press, 1968.