APA (7th ed.) Citation

Wahl, H., Siebert, J. S., & Tauber, B. (2017). Psychological theories of successful aging. Encyclopedia of geropsychology. https://doi.org/10.1007/978-981-287-082-7_108

Chicago Style (17th ed.) Citation

Wahl, Hans-Werner, Jelena Sophie Siebert, and Benjamin Tauber. "Psychological Theories of Successful Aging." Encyclopedia of Geropsychology 2017. https://doi.org/10.1007/978-981-287-082-7_108.

MLA (9th ed.) Citation

Wahl, Hans-Werner, et al. "Psychological Theories of Successful Aging." Encyclopedia of Geropsychology, 2017, https://doi.org/10.1007/978-981-287-082-7_108.