Bell, S. 1. J. 3., & Morse, S. (2008). Sustainability indicators: Measuring the immeasurable? (Second edition.). Earthscan.
Chicago-viite (17. p.)Bell, Simon 1957 July 30-, ja Stephen Morse. Sustainability Indicators: Measuring the Immeasurable? Second edition. London: Earthscan, 2008.
MLA-viite (9. p.)Bell, Simon 1957 July 30-, ja Stephen Morse. Sustainability Indicators: Measuring the Immeasurable? Second edition. Earthscan, 2008.
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