Student engagement and classroom variables in improving mathematics achievement
 Artikel Jurnal
Machin, John L.J.
The expectations approach : improving managerial communication and performance
McGraw-Hill, 1980
 Buku Teks
Lines, James
Profit improvement; a comprehensive approach to improving managerial effectiveness
Wiley, 1973
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The new approach to improving engineering education for an academic atmosphere
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Turban, Efraim, 1930-
Information technology for management : improving quality and productivity
John Wiley & Sons, 1996
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