Assessing representativeness of a probability-based online panel in Germany. In Online Panel Research: A Data Quality Perspective, edited by M. Callegaro, R. Baker, J. Bethlehem, A. Göritz, J. A. Krosnick, and P. J. Lavrakas, Wiley series in survey methodology, 61-84. New York: Wiley.
(xsd:string)