Zastrow, B. ., Martel, M. ., & Widiger, T. . (1969). Preschool Oppositional Defiant Disorder: A Disorder of Negative Affect, Surgency, and Disagreeableness. Journal of Clinical Child and Adolescent Psychology : The Official Journal for the Society of Clinical Child and Adolescent Psychology, American Psychological Association, Division 53, 47(6), 967-977. https://doi.org/10.1080/15374416.2016.1225504 (Original work published 1969)