Organisation for Economic Co-operation and Development & Seminar on Environmental Benefits from Agriculture. (1997). Environmental benefits from agriculture: Issues and policies : the Helsinki Seminar. Organisation for Economic Co-operation and Development ; OECD Washington Center [distributor].
Παραπομπή σε μορφή Chicago (17η εκδ.)Organisation for Economic Co-operation and Development και Seminar on Environmental Benefits from Agriculture. Environmental Benefits from Agriculture: Issues and Policies : The Helsinki Seminar. Paris : Washington D. C.: Organisation for Economic Co-operation and Development ; OECD Washington Center [distributor], 1997.
Παραπομπή σε μορφή MLA (8th εκδ.)Organisation for Economic Co-operation and Development και Seminar on Environmental Benefits from Agriculture. Environmental Benefits from Agriculture: Issues and Policies : The Helsinki Seminar. Organisation for Economic Co-operation and Development ; OECD Washington Center [distributor], 1997.