Columbia subject headings:
Bulls, Papal--Design--History.
Bulls, Papal--History.
Papacy--History--To 1309--Sources.
Harvard subject headings:
Bulls, Papal--Design--History.
Bulls, Papal--History.
Papacy--History--To 1309--Sources.
Princeton subject headings:
Bulls, Papal--Design--History.
Bulls, Papal--History.
Papacy--History--To 1309--Sources.