Austin, W. F. The Great Events by Famous Historians, Volume 05 (From Charlemagne to Frederick Barbarossa).
Citazione stile Chigago Style (17a edizione)Austin, Walter F. The Great Events by Famous Historians, Volume 05 (From Charlemagne to Frederick Barbarossa).
Citatione MLA (9a ed.)Austin, Walter F. The Great Events by Famous Historians, Volume 05 (From Charlemagne to Frederick Barbarossa).
Attenzione: Queste citazioni potrebbero non essere precise al 100%.