Rie, Juil, Younwook Kang, Jihyun Kim, and Kyung Ryu. 2011. “Generation Differences in Importance Perception of Productive Ageing and the Validity Analysis of Productive Ageing Scale”. Korean Journal of Industrial and Organizational Psychology 24 (1):1-27. https://doi.org/10.24230/kjiop.v24i1.1-27.