Columbia subject headings:
Environmental protection--Information services--Congresses.
Environmental sciences--Information services--Congresses.
Information resources management.
Harvard subject headings:
Environmental protection--Data processing--Congresses
Environmental protection--Information services--Congresses
Environmental sciences--Information services--Congresses.
Industrial management--Environmental aspects--Congresses.
Information resources management--Congresses
Information storage and retrieval systems--Environmental protection--Congresses.
Princeton subject headings: