Gaya APA

Foster, R, J., Griffin, E. (2000). Spiritual Classics : selected readings for individuals and groups on the twelve spiritual disciplines (Trawas) . San Francisco: Harper Collins Publishers.

Gaya MLA

Foster, Richard, J.., Griffin, Emilie. "Spiritual Classics : selected readings for individuals and groups on the twelve spiritual disciplines (Trawas)". San Francisco: Harper Collins Publishers, 2000. Text.