Tull,Donald S, & Hawkins,Del I. (1993). Marketing research: Measurement & method (6th ed.). Prentice-Hall of India Pvt. Ltd.
Chicago Style aipamenaTull,Donald S, and Hawkins,Del I. Marketing Research: Measurement & Method. 6th ed. New Delhi: Prentice-Hall of India Pvt. Ltd, 1993.
MLA aipamenaTull,Donald S, and Hawkins,Del I. Marketing Research: Measurement & Method. 6th ed. Prentice-Hall of India Pvt. Ltd, 1993.
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