APA استشهاد

Timothy Keller. (2008). Reason for god: Belief in an age of scepticism. Penguin group.

استشهاد بنمط شيكاغو

Timothy Keller. Reason for God: Belief in an Age of Scepticism. USA: Penguin group, 2008.

MLA استشهاد

Timothy Keller. Reason for God: Belief in an Age of Scepticism. Penguin group, 2008.