APA (7th ed.) Citation

Preston, R. J. (1947). Rocky mountain trees. The Iowa State College Press.

Chicago Style (17th ed.) Citation

Preston, Richard J. Rocky Mountain Trees. Ames, Iowa: The Iowa State College Press, 1947.

MLA (9th ed.) Citation

Preston, Richard J. Rocky Mountain Trees. The Iowa State College Press, 1947.

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