Humble, J. W. (1968). Improving business results. McGraw-Hill for Management Centre Europe.
Chicago-viite (17. p.)Humble, John William. Improving Business Results. Maidenhead: McGraw-Hill for Management Centre Europe, 1968.
MLA-viite (8. p.)Humble, John William. Improving Business Results. McGraw-Hill for Management Centre Europe, 1968.
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