Ellefson, P. V. (1992). Forest resources policy: Process, participants and programs. McGraw Hill.
Chicago-viite (17. p.)Ellefson, Paul V. Forest Resources Policy: Process, Participants and Programs. New York: McGraw Hill, 1992.
MLA-viite (8. p.)Ellefson, Paul V. Forest Resources Policy: Process, Participants and Programs. McGraw Hill, 1992.
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