Columbia subject headings:
Ecumenical movement--History--20th century.
Oriental Orthodox churches--Relations.
Orthodox Eastern Church--Relations.
Harvard subject headings:
Eastern churches--Relations--Sources.
Ecumenical movement--Eastern churches.
Ecumenical movement--Oriental Orthodox churches.
Ecumenical movement--Orthodox Eastern Church.
Oriental Orthodox churches--Relations--Orthodox Eastern Church--History--Sources.
Orthodox Eastern Church--Relations--History--Sources.
Orthodox Eastern Church--Relations--Oriental Orthodox Churches--History--Sources.
Princeton subject headings: