Mehrotra, Chandra Mohan
Distance learning : principles for effective design, delivery, and evaluation
Sage Publications, 2001
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Drucker, Peter Ferdinand, 1909-2005
The effective executive
Harper & Row, 1996
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Ficker, Victor B.
Effective supervision
Charles E. Merrill, 1975
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Gerber, Philip L.
Effective english
Random House, 1959
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Achua, Christopher F.
Effective leadership
South Western Cengage Learning, 2013
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