Brown, L. R., Renner, M., Starke, L., & Halweil, B. (2000). Vital signs 2000: The environmental trends that are shaping our future. Norton.
Cita Chicago (17th ed.)Brown, Lester Russell, Michael Renner, Linda Starke, i Brian Halweil. Vital Signs 2000: The Environmental Trends That Are Shaping Our Future. New York: Norton, 2000.
Cita MLA (8th ed.)Brown, Lester Russell, et al. Vital Signs 2000: The Environmental Trends That Are Shaping Our Future. Norton, 2000.
Atenció: Aquestes cites poden no estar 100% correctes.