Columbia subject headings:
Harvard subject headings:
Charles V, Holy Roman Emperor, 1500-1558.
Ferdinand I, Holy Roman Emperor, 1503-1564.
Holy Roman Empire--History--1517-1648--Sources.
Maurice, Elector of Saxony, 1521-1553.
Princeton subject headings:
Charles V, Holy Roman Emperor, 1500-1558.
Ferdinand I, Holy Roman Emperor, 1503-1564.