1. Long-term treatment of depression;Kupfer;J. Clin. Psychiatry,1991
2. Diagnostic and statistical manual of mental disorders,1994
3. Classification Internationale des troubles mentaux et des troubles du comportement. 10e version,1992
4. The course of monopolar depression and bipolar psychoses;Angst;Psychiatr. Neurol. Neurochir.,1973
5. Depression: a long-term illness;Keller;Br. J. Psychiatry,1994