Loffel, Egon W.
Financing your business
John Wiley & Sons, 1977
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Bratt, Elmer C.
Business forecasting
McGraw-Hill, 1958
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Hanke, Jonh E.
Business forecasting
Pearson Prentice Hall, 2005
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Hanke, John E.
Business forecasting
Prentice Halls, 2001
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Robinson, Colin
Business forecasting : an economic approach
Nelson, 1971
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