The historians' history of the world in twenty-five volumes, volume 07
CHAPTER VI. CHARLEMAGNE’S SUCCESSORS TO THE TREATY OF VERDUN
[b] VICTOR DURUY, _Histoire du Moyen Âge_.
[c] LEOPOLD VON RANKE, _Weltgeschichte_.
[d] AGOBARDUS, _Works_ (edited by Baluze).
[e] JOHANN G. A. WIRTH, _Geschichte der deutschen Staaten_.
[f] M. E. THALHEIMER, _Mediæval and Modern History_.