Columbia subject headings:
Literature, Medieval--History and criticism.
Mysticism--History--Middle Ages, 600-1500.
Visions in literature.
Visions--History of doctrines--Middle Ages, 600-1500.
Harvard subject headings:
Literature, Medieval--History and criticism
Mysticism--History--Middle Ages, 600-1500
Visions in literature
Visions--History of doctrines--Middle Ages, 600-1500.
Princeton subject headings:
Literature, Medieval--History and criticism.
Mysticism--History--Middle Ages, 600-1500.
Visions in literature.
Visions--History of doctrines--Middle Ages, 600-1500.