GZikmund, W. (2007). Essentials of marketing research (3.).
Lua i Stíl Chicago (17ú heag.)GZikmund, William. Essentials of Marketing Research. 3. Australia, 2007.
Lua MLA (9ú heag.)GZikmund, William. Essentials of Marketing Research. 3. 2007.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.