Luft, Joseph
Group processes: an introduction to dynamics
Mayfield Publishing Company, 1984
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Luft, Joseph
Group processes: an introduction to group dynamics
National Press Books, 1970
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The human environment
edited by Jonathan Rigg
Archipelago Press, 1996
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Treshow, Michael
The Human environment
McGraw-Hill, 1976
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Schey, John A.
Introduction to manufacturing processes
McGraw-Hill, 2000
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