1. Araki, C., Ishida, M., Okawa, I., Okawa, R., Kaneko, K., Saotome, T., & Watanabe, K. (2000). Sexuality in middle and advanced age: The dynamics of the partnership. The Japanese Assembly for the Study of Sex, 12(1), 2–18.
2. Araki, C., Ishida, M., Okawa, R., Kaneko, K., Horiguchi, S., & Horiguchi, M. (2014). Complete results from a 2012 survey of sexuality in the middle-aged. Japanese Journal of Sexology, 32(Suppl.), 68–116.
3. Armitage, P., Berry, G., & Matthews, J. N. S. (2008). Statistical methods in medical research (4th ed.). John Wiley & Sons.
4. Choi, K. B., Jang, S. H., Lee, M. Y., & Kim, K. H. (2011). Sexual life and self-esteem in married elderly. Archives of Gerontology and Geriatrics, 53(1), e17-20. https://doi.org/10.1016/j.archger.2010.08.011
5. Dello Buono, M., Urciuoli, O., & De Leo, D. (1998). Quality of life and longevity: A study of centenarians. Age and Ageing, 27(2), 207–216. https://doi.org/10.1093/ageing/27.2.207