Columbia subject headings:
Harvard subject headings:
Milan (Italy)--History--To 1535--Sources.
Milan (Italy)--Relations--Italy--Rome--Sources.
Rome (Italy)--Relations--Italy--Milan--Sources.
Princeton subject headings:
Diplomats--Italy--Rome--Correspondence.
Francesco Sforza, Duke of Milan, 1401-1466--Correspondence.
Nicholas V, Pope, 1397-1455--Correspondence.
Papacy--History--1447-1565--Sources.
Rome (Italy)--History--1420-1798--Sources.