APA (7th ed.) Citation

Ewert, S. D., & Rothman, H. (2004). Encyclopedia of American national parks. Sharpe Reference.

Chicago Style (17th ed.) Citation

Ewert, Sara Dant, and Hal Rothman. Encyclopedia of American National Parks. Armonk, N.Y.: Sharpe Reference, 2004.

MLA (9th ed.) Citation

Ewert, Sara Dant, and Hal Rothman. Encyclopedia of American National Parks. Sharpe Reference, 2004.