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Carson, H. L. 1975. The genetics of speciation at the diploid 

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Diamond, J. M. 1984. "Normal" extinctions of isolated 

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Harper, J.L. 1977. Population Biology of Plants. Academic 

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Lellinger, D. B. 1985. A field manual of the ferns and fern- 

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Lesica, P. 1987. A technique for monitoring nonrhizomatous 

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MacArthur, R. H. and E. 0. Wilson. 1967. The theory of island 

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Montgomery, J. D. 1990. Survivorship and predation changes in 

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Pimm, S. L. , H. L. Jones and J. Diamond. 1988. On the risk of 

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Templeton, A.R. 1980. The theory of speciation via the founder 

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Wagner, W. H. and F. S. Wagner. 1981. New species of moonworts, 

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