Columbia subject headings:
Ecology in literature--Congresses.
Nature in literature--Congresses.
Harvard subject headings:
Autobiography--Congresses
Biography as a literary form--Congresses
Ecology in literature--Congresses.
Literature--History and criticism--Congresses.
Nature in literature--Congresses.
Princeton subject headings:
Ecology in literature--Congresses.
Nature in literature--Congresses.