APA (7e ed.) Bronvermelding

Greer, P., & Lafferty, G. (2015). 40/40 vision: Clarifying your mission in midlife. IVP Books.

Chicago (17e ed.) Bronvermelding

Greer, Peter, en Greg Lafferty. 40/40 Vision: Clarifying Your Mission in Midlife. Downers Grove, IL: IVP Books, 2015.

MLA (9e ed.) Bronvermelding

Greer, Peter, en Greg Lafferty. 40/40 Vision: Clarifying Your Mission in Midlife. IVP Books, 2015.