Brown, L. R., Flavin, C., Renner, M., & Starke, L. (1999). Vital signs 1999: The environmental trends that are shaping our future. W.W. Norton.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रBrown, Lester Russell, Christopher Flavin, Michael Renner, और Linda Starke. Vital Signs 1999: The Environmental Trends That Are Shaping Our Future. New York: W.W. Norton, 1999.
एमएलए (8वां संस्करण) प्रशस्ति पत्रBrown, Lester Russell, et al. Vital Signs 1999: The Environmental Trends That Are Shaping Our Future. W.W. Norton, 1999.
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