Krueger, R. A. (1988). Focus groups: A practical guide for applied research. Sage Publications.
Lua i Stíl Chicago (17ú heag.)Krueger, Richard A. Focus Groups: A Practical Guide for Applied Research. Newbury Park, Calif.: Sage Publications, 1988.
Lua MLA (8ú heag.)Krueger, Richard A. Focus Groups: A Practical Guide for Applied Research. Sage Publications, 1988.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.