Cita APA (7a ed.)

Willis, R. E. (1971). The Ethics of Karl Barth. E.J. Brill.

Cita Chicago Style (17a ed.)

Willis, Robert E. The Ethics of Karl Barth. Leiden: E.J. Brill, 1971.

Cita MLA (9a ed.)

Willis, Robert E. The Ethics of Karl Barth. E.J. Brill, 1971.