APA (7th ed.) Citation

Engels, R. C., Kerr, M., & Stattin, H. (2007). Friends, lovers and groups: Key relationships in adolescence. John Wiley & Sons.

Chicago Style (17th ed.) Citation

Engels, Rutger C.M.E, Margaret Kerr, and Håkan Stattin. Friends, Lovers and Groups: Key Relationships in Adolescence. Chichester, England ; Hoboken, NJ: John Wiley & Sons, 2007.

MLA (9th ed.) Citation

Engels, Rutger C.M.E, et al. Friends, Lovers and Groups: Key Relationships in Adolescence. John Wiley & Sons, 2007.