Hackert, Adelbert F.
Elements of trigonometry / Adelbert F. Hackert and Charles L. Duff
D.C. Health and Company , 1971
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Nanney, J. Louis, author
Trigonometry : a skills approach, lecture version
Allyn and Bacon, 1980
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Taylor, Howard Edward
Contemporary trigonometry / Howard E. Taylor and Thomas L. wade
McGraw-Hill, 1973
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Tobey, John
Study guide to accompany Nanney and Cable's trigonometry / John Tobey and Henry Harmeling
Allyn and Bacon, 1980
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Brixey, John C., author
Modern trigonometry/ John C. Brixey
Henry Holt and Co., 1955
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