Não informado. (2022). US Forest Service Research Paper NE. Northeastern Forest Experiment Station.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. US Forest Service Research Paper NE. Upper Darby, Pa: Northeastern Forest Experiment Station, 2022.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. US Forest Service Research Paper NE. Northeastern Forest Experiment Station, 2022.
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