Part — Wouters, Manual of Moral Theology
Part VI. On the Sixth and Ninth Precepts of the Decalogue
752.
As regards the sixth precept of the Decalogue, which commands external chastity and prohibits sins opposed to it, and likewise as regards the ninth precept of the Decalogue, which regards internal chastity and the vices contrary to it, we refer to our little work pertaining to Moral Theology, whose title is De virtute castitatis et de vitiis oppositis.1
1 Published by Beyaert, Bruges.