Deferrari, Roy & Jerome Keeler. “St. Augustine’s City of God: Its Plan and Development.” American Journal of Philology, Vol. 50 (1929), pp. 109-37.  

Excerpt:

 

“Many statements have been made by scholars regarding the
plan and development of St. Augustine’s City of God, and while
they may be said to agree in the main, yet they are sometimes
contradictory in details, they are frequently vague, and always
very incomplete. The purpose of the present article is to pre-
sent, through the study of every available source, such a plan as
St. Augustine had in mind for the City of God while writing
it, and to show by a careful analysis of the work, how this plan
was actually carried out in the finished masterpiece itself.
In the second and third portions of this study we shall call
attention to anything in the form of a digression, repetition, or
unnecessary explanation that might be thought to mar the plan.
To our knowledge, no detailed study of the City of God from
this point of view is as yet in print.2”

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