Columbia subject headings:
Four elements (Philosophy) in literature--Congresses.
Four elements (Philosophy)--Congresses.
Literature, Medieval--Congresses.
Philosophy, Medieval--Congresses.
Harvard subject headings:
Four elements (Philosophy) in literature--Congresses.
Four elements (Philosophy)--Congresses.
Literature, Medieval--Congresses.
Philosophy, Medieval--Congresses.
Princeton subject headings:
Civilization, Medieval--Congresses.
Literature, Medieval--History and criticism--Congresses.
Science in literature--Congresses.
Science, Medieval--Congresses.