APA-viite (7. p.)
(1999). Voluntary approaches for environmental policy: An assessment. OECD Publications Services.
Chicago-viite (17. p.)
Voluntary Approaches for Environmental Policy: An Assessment. Paris, France: OECD Publications Services, 1999.
MLA-viite (9. p.)
Voluntary Approaches for Environmental Policy: An Assessment. OECD Publications Services, 1999.
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