APA (7th ed.) Citation

Calkins, G. N. (1909). Protozoölogy. Lea and Febiger.

Chicago Style (17th ed.) Citation

Calkins, Gary N. Protozoölogy. New York and Philadelphia: Lea and Febiger, 1909.

MLA (9th ed.) Citation

Calkins, Gary N. Protozoölogy. Lea and Febiger, 1909.