Columbia subject headings:
Church--History of doctrines.
Death--Religious aspects--Christianity--History of doctrines.
Eschatology--History of doctrines.
Intermediate state--History of doctrines.
Harvard subject headings:
Catholic Church--Doctrines.
Church
Church--History of doctrines.
Eschatology.
Purgatory--History of doctrines
Suffering--Religious aspects--Catholic Church
Princeton subject headings: