Columbia subject headings:
Harvard subject headings:
English poetry--Middle English, 1100-1500
English poetry--Middle English, 1100-1500--History and criticism
English poetry--Old English, ca. 450-1100
English poetry--Old English, ca. 450-1100--History and criticism
Princeton subject headings:
English poetry--Middle English, 1100-1500--History and criticism.
English poetry--Middle English, 1100-1500.
English poetry--Old English, ca. 450-1100--History and criticism.
English poetry--Old English, ca. 450-1100.