Columbia subject headings:
Monastic and religious life--History--Middle Ages, 600-1500--Sources.
Orthodox Eastern monasticism and religious orders--History--Sources.
Harvard subject headings:
Monastic and religious life--History--Middle Ages, 600-1500--Sources.
Orthodox Eastern monasticism and religious orders--History--Sources.
Theodore, Studites, Saint, 759-826. Correspondence.
Princeton subject headings:
Orthodox Eastern Church--Byzantine Empire--Clergy--Correspondence.
Orthodox Eastern Church--History--Sources.
Theodore, Studites, Saint, 759-826. Correspondence.