Brown, L. R., Renner, M., Flavin, C., & Starke, L. (1997). Vital signs, 1997: The environmental trends that are changing our future. Earthscan.
Chicago-referens (17:e uppl.)Brown, Lester Russell, Michael Renner, Christopher Flavin, och Linda Starke. Vital Signs, 1997: The Environmental Trends That Are Changing Our Future. London: Earthscan, 1997.
MLA-referens (8:e uppl.)Brown, Lester Russell, et al. Vital Signs, 1997: The Environmental Trends That Are Changing Our Future. Earthscan, 1997.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.