Columbia subject headings:
Ecumenical movement.
Holy Spirit--Procession--History of doctrines.
Trinity--History of doctrines.
Harvard subject headings:
Catholic Church--Relations--Orthodox Eastern Church.
Christian union.
Holy Spirit--Procession--History of doctrines.
Jesus Christ--Procession--History of doctrines.
Orthodox Eastern Church--Relations--Catholic Church.
Orthodox Eastern Church--Relations--Protestant churches.
Protestant churches--Relations--Orthodox Eastern Church.
Trinity--History of doctrines.
Princeton subject headings: