Columbia subject headings:
Environmental protection--Vocational guidance--United States.
Environmental protection--Vocational guidance.
Natural resources--Management--Vocational guidance.
Natural resources--United States--Management--Vocational guidance.
Harvard subject headings:
Environmental protection--Vocational guidance
Environmental protection--Vocational guidance--United States.
Natural resources--Management--Vocational guidance--United States.
Natural resources--Management--Vocational guidance.
Princeton subject headings: