Columbia subject headings:
Catholic Church. Patriarchate of Aquileia (Italy)--History--Middle Ages, 600-1500.
Church history--Middle Ages, 600-1500.
Papacy--History.
Harvard subject headings:
Catholic Church. Patriarchate of Aquileia (Italy)--History.
Papacy--History--1309-1378
Papacy--History--To 1309
Schmidinger, Heinrich.
Princeton subject headings: