APA (7th ed.) Citation

Thielicke, H. (1968). I believe: The Christian's creed. Fortress Press.

Chicago Style (17th ed.) Citation

Thielicke, Helmut. I Believe: The Christian's Creed. Philadelphia: Fortress Press, 1968.

MLA (9th ed.) Citation

Thielicke, Helmut. I Believe: The Christian's Creed. Fortress Press, 1968.

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