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.
Princeton subject headings:
Charles V, Holy Roman Emperor, 1500-1558.
Ferdinand I, Holy Roman Emperor, 1503-1564.
Holy Roman Empire--History--1517-1648.