Negative mood regulation expectancies, self-efficacy beliefs, and locus of control orientation: moderators or mediators of change in the treatment of depression? - Backenstraß, Matthias; Schwarz, Thomas; Fiedler, Peter; Joest, Katharina; Reck, Corinna; Mundt, Christoph; Kronmüller, Klaus-Thomas (Psychotherapy research, 2006)