Columbia subject headings:
Harvard subject headings:
Arthur, King--In literature.
Arthur, King.
Arthurian romances--Adaptations--History and criticism.
Arthurian romances--Adaptations.
Arthurian romances--History and criticism.
Princeton subject headings:
Arthur, King
Arthurian legends--History and criticism.
Arthurian romances--History and criticism.
Merlin (Legendary character)--Legends--History and criticism.
Merlin (Legendary character).