Cita APA (7a ed.)

Snyder, P. V., & Coggin, R. (1977). The Christmas tree book: The history of the Christmas tree and antique Christmas tree ornaments. Penguin Books.

Cita Chicago Style (17a ed.)

Snyder, Phillip V., y Roy Coggin. The Christmas Tree Book: The History of the Christmas Tree and Antique Christmas Tree Ornaments. Harmondsworth, Eng. ; New York: Penguin Books, 1977.

Cita MLA (8a ed.)

Snyder, Phillip V., y Roy Coggin. The Christmas Tree Book: The History of the Christmas Tree and Antique Christmas Tree Ornaments. Penguin Books, 1977.