Brubaker, O. J. (1972). Understanding people. Evangelical Teacher Training Association.
Čikaški stil citiranja (17. izdanje)Brubaker, Omar J. Understanding People. Evangelical Teacher Training Association, 1972.
MLA način citiranja (9. izdanje)Brubaker, Omar J. Understanding People. Evangelical Teacher Training Association, 1972.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.