1. “To Answer or Not to Answer: Decision Processes Related to Survey Item Nonresponse.”,2002
2. “Vague Quantifiers.”;Public Opinion Quarterly,1979
3. “Prevention and Treatment of Item Nonresponse.”;Journal of Official Statistics,2003
4. “Designing a Strategy for Reducing ‘No Opinion’ Responses in Web-Based Surveys.”;Social Science Computer Review,2002
5. “Comparing Data from Online and Face-to-Face Surveys.”;International Journal of Market Research,2005