APA (7th ed.) Citation

Katz, E., & Lazarasfeid, P. F. (1955). Personal influence; the part played by people in the flow of mass communications. Free Press.

Chicago Style (17th ed.) Citation

Katz, Elihu, and Paul Felix Lazarasfeid. Personal Influence; the Part Played by People in the Flow of Mass Communications. New York: Free Press, 1955.

MLA (9th ed.) Citation

Katz, Elihu, and Paul Felix Lazarasfeid. Personal Influence; the Part Played by People in the Flow of Mass Communications. Free Press, 1955.