The Cambridge medieval history /
edited by J.M. Hussey ; with the editorial assistance of D.M. Nicol, G. Cowan 
. - Cambridge : University Press,  1949- 
. - v.  24 cm. 
<br/> V. 4. The Byzantine Empire. Pt. 1. Byzantium and its Neighbours  <br/>  V. 4. The Byzantine Empire. Pt. 2. Government, church and civilisation  <br/>  V. 7. Decline of empire and papacy  <br/>  <br/>