Wahl Hans-Werner, Deeg Dorly J H
Department of Psychological Ageing Research, Institute of Psychology, University of Heidelberg, Bergheimer Straße 20, 69115 Heidelberg, Germany.
VU University Medical Center, Van der Boechorstraat 7, 1081 BT Amsterdam, The Netherlands.
Eur J Ageing. 2009 Feb 26;6(1):1-2. doi: 10.1007/s10433-009-0106-z. eCollection 2009 Mar.