APA (7th ed.) Citation

Zobel, D. B., & Zeigler, R. S. (1978). Lodgepole pine at Crater Lake: History and management of the forest structure. [National Park Service?].

Chicago Style (17th ed.) Citation

Zobel, Donald B., and Robert S. Zeigler. Lodgepole Pine at Crater Lake: History and Management of the Forest Structure. [Seattle, Wash.?]: [National Park Service?], 1978.

MLA (9th ed.) Citation

Zobel, Donald B., and Robert S. Zeigler. Lodgepole Pine at Crater Lake: History and Management of the Forest Structure. [National Park Service?], 1978.