RT Article T1 The self-concept over time: research issues and directions JF Annual review of sociology VO 18 SP 303 OP 326 A1 Demo, David H. LA English YR 1992 UL https://krimdok.uni-tuebingen.de/Record/163943710X K1 Lebenslaufforschung K1 Selbstkonzept K1 Soziale Reifungsprozesse