Posey, Imogene A.
Harcourt Brace Jovanovich, 1990
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Metcalf, Richard W., author
Harcourt Brace Jovanovich, 1990
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Hanson, A.H.
Oxford University Press, 1966
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Mayfield Publishing Company, 2000
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Wells, Lisa K., author
Prentice-Hall, 1995
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