Tul,Donald S, & Hawkins,Del I. Marketing research: Measurement and method (2nd ed.). Collier Macmillan International.
Dyfyniad Arddull ChicagoTul,Donald S, and Hawkins,Del I. Marketing Research: Measurement and Method. 2nd ed. New York: Collier Macmillan International.
Dyfyniad MLATul,Donald S, and Hawkins,Del I. Marketing Research: Measurement and Method. 2nd ed. Collier Macmillan International.
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