Columbia subject headings:
Cardinals--Italy--Guastalla--Biography.
Gonzaga di Guastalla, Francesco, 1538-1566--Correspondence.
Gonzaga di Guastalla, Francesco, 1538-1566.
Pius IV, Pope, 1499-1565.
Harvard subject headings:
Cardinals--Italy--Guastalla--Biography.
Catholic Church--History--16th century.
Gonzaga di Guastalla, Francesco, 1538-1566--Correspondence.
Gonzaga di Guastalla, Francesco, 1538-1566.
Princeton subject headings:
Catholic Church--History--16th century.
Gonzaga di Guastalla, Francesco, 1538-1566--Correspondence.
Gonzaga di Guastalla, Francesco, 1538-1566.