Não informado. (1963). US Forest Service Research Paper PNW. U.S. Forest Service.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. US Forest Service Research Paper PNW. Portland, Ore: U.S. Forest Service, 1963.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. US Forest Service Research Paper PNW. U.S. Forest Service, 1963.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.