Columbia subject headings:
Poetics--History.
Poetry, Medieval--History and criticism.
Semiotics--History.
Harvard subject headings:
Poetics--History
Poetics--History--To 1500
Poetry, Medieval--History and criticism--Theory, etc.
Poetry, Medieval--History and criticism.
Semiotics--History--To 1500.
Semiotics--History.
Princeton subject headings:
Poetics--History.
Poetry, Medieval--History and criticism.
Semiotics--History.