Berkhof, L. (1941). Systematic theology: With a complete textual index (4th ed.). Wm. B. Eerdmans.
Lua i Stíl Chicago (17ú heag.)Berkhof, L. Systematic Theology: With a Complete Textual Index. 4th ed. Michigan: Wm. B. Eerdmans, 1941.
Lua MLA (9ú heag.)Berkhof, L. Systematic Theology: With a Complete Textual Index. 4th ed. Wm. B. Eerdmans, 1941.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.