APA
Gordis L., . (2009). Epidemiology. Philadelphia: Saunders.
Chicago
Gordis Leon, . 2009. Epidemiology. Philadelphia: Saunders.
Harvard
Gordis L., . (2009). Epidemiology. Philadelphia: Saunders.
MLA
Gordis Leon, . Epidemiology. Philadelphia: Saunders. 2009.