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Karen A. Harper, G. Peter Kershaw, Natural Revegetation on Borrow Pits and Vehicle Tracks in Shrub Tundra, 48 Years Following Construction of the CANOL No. 1 Pipeline, N.W.T., Canada, Arctic and Alpine Research, Vol. 28, No. 2 (May, 1996), pp. 163-171
Harper et al. (Wed,) studied this question.