Engelman, R., & LeRoy, P. (1993). Sustaining water: Population and the future of renewable water supplies. Washington: Population Action International.
Chicago-viite (17. p.)Engelman, Robert, ja Pamela LeRoy. Sustaining Water: Population and the Future of Renewable Water Supplies. Washington: Population Action International, 1993.
MLA-viite (8. p.)Engelman, Robert, ja Pamela LeRoy. Sustaining Water: Population and the Future of Renewable Water Supplies. Washington: Population Action International, 1993.
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