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Questionnaire design : how to plan, structure and write survey material for effective market research
Brace, Ian, (2008)
The practice of market research : an introduction
MacGivern, Yvonne, (2009)
Moderne Methoden der Marktforschung : Kunden besser verstehen
Gansser, Oliver A., (2017)
Brace, Ian, (2013)