Cita APA (7th ed.)
Hallesby,O. (1973). Prayer (1st ed.). Intervarsity Press.
Cita Chicago (17th ed.)
Hallesby,O. Prayer. 1st ed. Bedford square,London: Intervarsity Press, 1973.
Cita MLA (9th ed.)
Hallesby,O. Prayer. 1st ed. Intervarsity Press, 1973.
Atenció: Aquestes cites poden no estar 100% correctes.