Columbia subject headings:
Epic literature, Spanish--History and criticism.
Romances, Spanish--History and criticism.
Harvard subject headings:
Ballads, Spanish--History and criticism.
Cantar de mío Cid.
Cid, approximately 1043-1099--Romances--History and criticism.
Epic poetry, Spanish--History and criticism.
Princeton subject headings:
Epic poetry, Spanish--History and criticism.
Romances, Spanish--History and criticism.