[1]
A. Opsal, Øistein Kristensen, T. Ruud, T. K. Larsen, R. W. Gråwe, and T. Clausen, “Substance abuse in patients admitted voluntarily and involuntarily to acute psychiatric wards: a national cross-sectional study”, Nor J Epidemiol, vol. 21, no. 1, Dec. 2011.