1. Improving mailed questionnaires: Analysis of a 96 percent return rate;Altschuld,1984
2. Increasing mail questionnaire response in large samples of the general public;Dillman;Public Opinion Quarterly,1972
3. Mail and telephone surveys;Dillman,1978
4. The importance of adhering to details of the Total Design Method (TDM) for mail surveys;Dillman,1984
5. The effect of telephone versus letter prenotification on mail survey response rate, speed, quality and cost;Faria;Journal of the Market Research Society,1990