APA Style

Knapp, M, L., Hall, J, A. (2006). Nonverbal communication in human interaction. Sixth Edition (Sixth Edition). Belmont, California: Thomson/Wadsworth.

MLA Style

Knapp, Mark, L., Hall, Judith, Al. "Nonverbal communication in human interaction. Sixth Edition". Sixth Edition Belmont, California: Thomson/Wadsworth, 2006. Text.