Cita APA (7th ed.)

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

Cita Chicago (17th ed.)

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

Cita MLA (9th ed.)

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