A programed course in calculus : V infinite sequences and series
by Howard W. Alexander... [et.al.]
W.A. Benjamin, 1968
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Makkink, H.J.
An English grammar
Nijgh and Van Ditmar, 1951
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Helling, Pam
The grammar and proofreading course
[American Management Association, ], 1992
 eBooks
Harder, Paul O
Basic materials in music theory a programed course/Paul O. Harder
Allyn and Bacon , 1975
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Beason, Larry
A Commonsense guide to grammar and usage
Bredfors/ St. Martins, 2003
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