How to preserve the antidepressive effect of sleep deprivation: A comparison of sleep phase advance and sleep phase delay. - Riemann, D.; König, A.; Hohagen, F.; Kiemen, A.; Voderholzer, U.; Backhaus, J.; Bunz, J.; Wesiack, B.; Hermle, L.; Berger, M. (European Archives of Psychiatry & Clinical Neuroscience, 1999)