The Cambridge Ancient History volume XIV. Late Antiquity: Empire and Successors A.D. 425-600. Edited by Averil Cameron, Bryan Ward-Perkins, and Michael Whitby. Cambridge University Press 2000. ISBN 978-0-521-32591-2. Part III East and West: Economy and Society. Chapter 12. Land, labor, and settlement, by Bryan Ward-Perkins. Page 333.