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Dyfyniad Arddull ChicagoSundel, Martin, and Sandra Stone Sundel. Behavior Change in the Human Services: Behavioral and Cognitive Principles and Applications. 5th ed. Thousand Oaks, Calif: Sage Publications, 2005.
Dyfyniad MLASundel, Martin, and Sandra Stone Sundel. Behavior Change in the Human Services: Behavioral and Cognitive Principles and Applications. 5th ed. Sage Publications, 2005.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.