Lua APA (7ú heag.)
Keller, W. P. (1993). Strength of soul: The sacred use of time. Kregel Publications.
Lua i Stíl Chicago (17ú heag.)
Keller, W. Phillip. Strength of Soul: The Sacred Use of Time. Grand Rapids, MI: Kregel Publications, 1993.
Lua MLA (9ú heag.)
Keller, W. Phillip. Strength of Soul: The Sacred Use of Time. Kregel Publications, 1993.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.