Cita APA (7a ed.)

Duncan, R. (1947). Heavenly City; Earthly City. B. Porter.

Cita Chicago Style (17a ed.)

Duncan, Robert. Heavenly City; Earthly City. Berkeley: B. Porter, 1947.

Cita MLA (9a ed.)

Duncan, Robert. Heavenly City; Earthly City. B. Porter, 1947.