Fowler, F. J., & Floyd J. Fowler; Jr. Survey research methods. Thousand Oaks, Calif: Sage Publications.
Chicago Style aipamenaFowler, Floyd J., và Floyd J. Fowler; Jr. Survey Research Methods. Thousand Oaks, Calif: Sage Publications.
MLA aipamenaFowler, Floyd J., và Floyd J. Fowler; Jr. Survey Research Methods. Thousand Oaks, Calif: Sage Publications.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.