Peterson, J. A., & Tuxill, J. D. (1998). Losing strands in the web of life: Vertebrate declines and the conservation of biological diversity. Worldwatch Institute.
Chicago-viite (17. p.)Peterson, Jane A., ja John D. Tuxill. Losing Strands in the Web of Life: Vertebrate Declines and the Conservation of Biological Diversity. Washington, DC: Worldwatch Institute, 1998.
MLA-viite (9. p.)Peterson, Jane A., ja John D. Tuxill. Losing Strands in the Web of Life: Vertebrate Declines and the Conservation of Biological Diversity. Worldwatch Institute, 1998.
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