Columbia subject headings:
Catholic Church--Foreign relations--Mexico--19th century.
Herrera, José Joaquín de, 1792-1854--Correspondence.
Italy--History--Revolution of 1848.
Mexico--Foreign relations--Catholic Church--19th century.
Pius IX, Pope, 1792-1878--Correspondence.
Pius IX, Pope, 1792-1878--Exile--Italy--Gaeta.
Harvard subject headings:
Catholic Church--Foreign relations--Mexico--19th century.
Herrera, José Joaquín de, 1792-1854--Correspondence.
Italy--History--Revolution of 1848.
Mexico--Foreign relations--Catholic Church--19th century.
Pius IX, Pope, 1792-1878--Correspondence.
Pius IX, Pope, 1792-1878--Exile--Italy--Gaeta.
Princeton subject headings: