Chapter VI will be devoted specifically to Justice, Distributive and Corrective, although every chapter will, in its way, be about this topic. The major sources are, of course, The Nichomachean Ethics and St. Thomas's commentary on the same, as well as the Summa. But it is a case of Philosophy is easy, plumbing is hard. Distributive justice is easy to see and understand philosophically, but its implementation in the real world, its "plumbing" is very hard indeed.
Looking forward to Chapter 6!