Columbia subject headings:
Harvard subject headings:
Free trade--Papal States--History.
Papal States--Commercial policy--History.
Tariff--Papal States--History.
Tolls--Papal States--History.
Princeton subject headings:
Benedict XIV, Pope, 1675-1758.
Food law and legislation--Italy--Papal States--History.
Food prices--Government policy--Italy--Papal States--History.
Food supply--Government policy--Italy--Papal States--History.
Privileges and immunities--Italy--Papal States--History.