APA (7th ed.) Citation

Strickler, D. (1997). Northwest penstemons: 80 species of Penstemon native to the Pacific Northwest. Flower Press.

Chicago Style (17th ed.) Citation

Strickler, Dee. Northwest Penstemons: 80 Species of Penstemon Native to the Pacific Northwest. Columbia Falls, Mont.: Flower Press, 1997.

MLA (8th ed.) Citation

Strickler, Dee. Northwest Penstemons: 80 Species of Penstemon Native to the Pacific Northwest. Flower Press, 1997.

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