Easterly, William Russell
The white man's burden : why the West?s efforts to aid the rest have done so much ill and so little good
Penguin Press, 2006
 Buku Teks SO
Gittleman, Ann Louise
Why Am I Always so Tired?
HarperSanFrancisco, 1999
 Buku Teks SO
Gittleman, Ann Louise
Why Am I Always so Tired?
HarperSanFrancisco, 1999
 Buku Teks SO
Cheskin, Louis
Why people by : motivation research and its successful application
Liveright, 1959
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Richards, Larry E.
Business statistics : why and when
McGraw-Hill, 1983
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