Menichetti, J., A. Bonanomi, and G. Graffigna. “The Engagement in Healthy Ageing Promotion Scale: Development and Validation”. JOURNAL OF GERONTOLOGY AND GERIATRICS, Vol. 66, no. 1, Mar. 2018, pp. 7-14, http://www.jgerontology-geriatrics.com/article/view/96.