North, M. P. (1990). Old growth research areas of the Department of Natural Resources. Washington State Dept. of Natural Resources.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNorth, Malcolm P. Old Growth Research Areas of the Department of Natural Resources. [Olympia, Wash.]: Washington State Dept. of Natural Resources, 1990.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNorth, Malcolm P. Old Growth Research Areas of the Department of Natural Resources. Washington State Dept. of Natural Resources, 1990.
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