Brown, L. R., Renner, M., Flavin, C., & Starke, L. (1997). Vital signs, 1997: The environmental trends that are changing our future. Earthscan.
Chicago-viite (17. p.)Brown, Lester Russell, Michael Renner, Christopher Flavin, ja Linda Starke. Vital Signs, 1997: The Environmental Trends That Are Changing Our Future. London: Earthscan, 1997.
MLA-viite (8. p.)Brown, Lester Russell, et al. Vital Signs, 1997: The Environmental Trends That Are Changing Our Future. Earthscan, 1997.
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