Cohen, D Research problems and concepts in the study of aging: assessment and behavior modification. [electronic resource] - The Gerontologist Jun 1967 - 13-9 p. digital Publication Type: Journal Article; Review ISSN: 0016-9013 Standard No.: 10.1093/geront/7.2_part_2.13 doi Subjects--Topical Terms: AgedAgingBehaviorBehavior TherapyConditioning, PsychologicalGeriatricsHumansLearningMiddle AgedPersonalityPersonality AssessmentPsychotherapyResearch