APA (7th ed.) Citation

Hallesby, O. (1964). Why I Am A Christian. Inter-Varsity Fellowship.

Chicago Style (17th ed.) Citation

Hallesby, O. Why I Am A Christian. Inter-Varsity Fellowship, 1964.

MLA (8th ed.) Citation

Hallesby, O. Why I Am A Christian. Inter-Varsity Fellowship, 1964.

Warning: These citations may not always be 100% accurate.