Covey, S. R. 7 Habits of Highly effective People (7 kebiasaan Manusia Yang Sangat efektif). Binarupa Aksara.
Dyfyniad Arddull ChicagoCovey, Stephen R. 7 Habits of Highly Effective People (7 Kebiasaan Manusia Yang Sangat Efektif). Binarupa Aksara.
Dyfyniad MLACovey, Stephen R. 7 Habits of Highly Effective People (7 Kebiasaan Manusia Yang Sangat Efektif). Binarupa Aksara.
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