Dunckel, E. B. (1970). The business environment of the seventies: A trend analysis for business planning. New York: McGraw- Hill.
Dyfyniad Arddull ChicagoDunckel, Earl B. The Business Environment of the Seventies: A Trend Analysis for Business Planning. New York: McGraw- Hill, 1970.
Dyfyniad MLADunckel, Earl B. The Business Environment of the Seventies: A Trend Analysis for Business Planning. New York: McGraw- Hill, 1970.
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