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2. Radforth, N. W., Organic Terrain Organization from the Air (Handbook No. 2, Defense Research Board, Dept. Nat. Defense, DR No. 124, Ottawa, 1958).
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4. Radforth, N. W., in Muskeg Engineering Handbook (edit. by MacFarlane, I. V.) (University of Toronto Press, 1969).
5. Johnson, A. W., Viereck, L. A., Johnson, R. E., and Melchoir, H., in The Environment of Cape Thompson Region Alaska, 277 (US Atomic Energy Commission, 1965).