Não informado. (1963). US Forest Service Research Paper PNW. U.S. Forest Service.
Chicago (17e ed.) BronvermeldingNão informado. US Forest Service Research Paper PNW. Portland, Ore: U.S. Forest Service, 1963.
MLA (8e ed.) BronvermeldingNão informado. US Forest Service Research Paper PNW. U.S. Forest Service, 1963.
Let op: Deze citaties zijn niet altijd 100% accuraat.