APA (7th ed.) Citation

Costas, O. E. (1982). Christ outside the gate: Mission beyond christendom. Orbis.

Chicago Style (17th ed.) Citation

Costas, Orlando E. Christ Outside the Gate: Mission Beyond Christendom. New York: Orbis, 1982.

MLA (9th ed.) Citation

Costas, Orlando E. Christ Outside the Gate: Mission Beyond Christendom. Orbis, 1982.