Não informado. (2022). US Forest Service Resource Bulletin NE. Northeastern Forest Experiment Station.
Chicago-viite (17. p.)Não informado. US Forest Service Resource Bulletin NE. Upper Darby, Pa: Northeastern Forest Experiment Station, 2022.
MLA-viite (8. p.)Não informado. US Forest Service Resource Bulletin NE. Northeastern Forest Experiment Station, 2022.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.