@book{128537,
	author = {Hawkins, Del I. and Tull, Donald S.,},
	title = {Essentials of marketing research},
	publisher = {Macmillan Publishing Co.},
	year = {1993.},
	address = {New York},
	note = {Portions of this book are taken from the authors' Marketing research, 6th ed., published in 1993.}
}