Cita APA (7a ed.)

Porterfield, K. M. (1989). Violent voices: 12 steps to freedom from verbal and emotional abuse.

Cita Chicago Style (17a ed.)

Porterfield, Kay Marie. Violent Voices: 12 Steps to Freedom from Verbal and Emotional Abuse. Deerfield Beach, Fla, 1989.

Cita MLA (8a ed.)

Porterfield, Kay Marie. Violent Voices: 12 Steps to Freedom from Verbal and Emotional Abuse. 1989.