Não informado. (2022). US Forest Service Resource Bulletin NC. North Central Forest Experiment Station.
Chicago-viite (17. p.)Não informado. US Forest Service Resource Bulletin NC. Saint Paul, Minn: North Central Forest Experiment Station, 2022.
MLA-viite (8. p.)Não informado. US Forest Service Resource Bulletin NC. North Central Forest Experiment Station, 2022.
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