Penafiel, S. R. (1982). Effects of three pasture plant extracts on germination of Benguet pine (pinus kesiya royle ex gordon).
Chicago-viite (17. p.)Penafiel, Samuel R. Effects of Three Pasture Plant Extracts on Germination of Benguet Pine (pinus Kesiya Royle Ex Gordon). 1982.
MLA-viite (9. p.)Penafiel, Samuel R. Effects of Three Pasture Plant Extracts on Germination of Benguet Pine (pinus Kesiya Royle Ex Gordon). 1982.
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