1. Willis T: Pharmaceutice rationalis sive diatriba de medicamentorum operationibus in humano corpore. 1675, Oxford: E Theatro Sheldoniano
2. Ridner SH: Psychological distress: concept analysis. Journal of advanced nursing. 2004, 45 (5): 536-545. 10.1046/j.1365-2648.2003.02938.x.
3. Hahn D, Reuter K, Harter M: Screening for affective and anxiety disorders in medical patients - comparison of HADS, GHQ-12 and Brief-PHQ. Psychosoc Med. 2006, 3: 9-
4. Goldberg DP, Gater R, Sartorius N, Ustun TB, Piccinelli M, Gureje O, Rutter C: The validity of two versions of the GHQ in the WHO study of mental illness in general health care. Psychol Med. 1997, 27 (1): 191-197. 10.1017/S0033291796004242.
5. Knol MJ, Twisk JW, Beekman AT, Heine RJ, Snoek FJ, Pouwer F: Depression as a risk factor for the onset of type 2 diabetes mellitus. A meta-analysis. Diabetologia. 2006, 49 (5): 837-845.