"Pacific Grove: Brooks/Cole Publishing Company, 1998",
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Hill, John William, 1933-, author
Upper Saddle RIver Prentice Hall 1997,
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Beyer, Hans, author
[Publisher not identified], [Date of publication not identified]
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Solomons, T. W. Graham, author
John Wiley & Sons, 1992
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Fessenden, Ralph J., author
Wadsworth, 1979
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