Kaufman, P. B. (1979). Plants, People & Environment Peter B. Kaufman And J. Donald Lacroix. Macmillan.
Lua i Stíl Chicago (17ú heag.)Kaufman, Peter B. Plants, People & Environment Peter B. Kaufman And J. Donald Lacroix. Macmillan, 1979.
Lua MLA (8ú heag.)Kaufman, Peter B. Plants, People & Environment Peter B. Kaufman And J. Donald Lacroix. Macmillan, 1979.
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