MLA

Markus, Robert Austin. Christianity In the Roman World. New York (N.Y.): Scribner, 1974.

APA

Markus, R. Austin. (1974). Christianity in the Roman world. New York (N.Y.): Scribner.

Chicago

Markus, Robert Austin, Christianity In the Roman World. New York (N.Y.): Scribner, 1974.