Não informado. (2000). Technical notes. U.S. Lake States Forest Experiment Station.
Chicago-viite (17. p.)Não informado. Technical Notes. Saint Paul, Minn: U.S. Lake States Forest Experiment Station, 2000.
MLA-viite (8. p.)Não informado. Technical Notes. U.S. Lake States Forest Experiment Station, 2000.
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