Markward of Anweiler and the Sicilian regency; a study of Hohenstaufen policy in Sicily during the minority of Frederick II,

by Van Cleve, Thomas Curtis, 1888-, Van Cleve, Thomas Curtis, 1888-1976, Van Cleve, Thomas Curtis, 1888-1976
Published 1937

The Emperor Frederick II of Hohenstaufen, immutator mundi

by Van Cleve, Thomas Curtis, 1888-, Van Cleve, Thomas Curtis, 1888-1976
Published 1972