Columbia subject headings:
Catholic Church--Relations--Orthodox Eastern Church.
Holy Spirit--Procession--Early works to 1800.
Orthodox Eastern Church--Relations--Catholic Church.
Harvard subject headings:
Catholic Church--Relations--Orthodox Eastern Church.
Holy Spirit--Procession--Early works to 1800.
Orthodox Eastern Church--Relations--Catholic Church.
Princeton subject headings:
Catholic Church--Relations--Orthodox Eastern Church.
Holy Spirit--Procession--Early works to 1800.
Orthodox Eastern Church--Relations--Catholic Church.