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3. Archer, S., Scifres, C., Bassham, C., and Maggio, R.: 1988, ?Autogenic Succession in a Subtropical Savanna: Rates, Dynamics and Processes in the Conversion of Grassland to Thorn Woodland?,Ecol. Monogr. 58, 111?127.
4. Bahre, C. J.: 1991,A Legacy of Change: Historic Human Impact on Vegetation of the Arizona Borderlands, Univ. Arizona Press, Tucson, 231 pp.
5. Baisan, C. H. and Swetnam, T. W.: 1990, ?Fire History on a Desert Mountain Range: Rincon Mountain Wilderness, Arizona, USA?,Can. J. For. Res. 20, 1559?1569.