Rubel Foundation. (1999). Perspectives in Plant Ecology, Evolution and Systematics. Urban & Fischer Verlag.
Chicago-viite (17. p.)Rubel Foundation. Perspectives in Plant Ecology, Evolution and Systematics. Jena, Alemanha: Urban & Fischer Verlag, 1999.
MLA-viite (8. p.)Rubel Foundation. Perspectives in Plant Ecology, Evolution and Systematics. Urban & Fischer Verlag, 1999.
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