Henkel, V., Seemüller, F., Obermeier, M., Adli, M., Bauer, M., Kronmüller, K., Holsboer, F., Brieger, P., Laux, G., Bender, W., Heuser, I., Zeiler, J., Gaebel, W., Mayr, A., Riedel, M., & Möller, H. J. (2011). Relationship between Baseline Severity of Depression and Antidepressant Treatment Outcome. Pharmacopsychiatry, 44(1), 27-32.