Gater, R., Tansella, M., Korten, A., Tiemens, BG.,
Mavreas, VG. & Olatawura, MO., mei-1998, In:
Archives of General Psychiatry.55, 5,
blz. 405-4139 blz.
ORMEL, J., VONKORFF, M.,
USTUN, TB., PINI, S., KORTEN, A. & OLDEHINKEL, T., 14-dec.-1994, In:
JAMA-JOURNAL OF THE AMERICAN MEDICAL
ASSOCIATION.272, 22, blz. 1741 -
17488 blz.