title: [Theoretical principles of preparing for an active old age].
mesh_terms: D000368:Aged / Q000523:psychology*; D000375:Aging; D005260:Female; D006801:Humans; D008297:Male; D008603:Mental Health; D012179:Retirement; D012931:Social Environment
vernacular_title: Theoretische Grundlagen der Vorbereitung auf ein aktives Alter.