Остров Вашон: K. Rietberg, C. DeBolt, N. Heimann, et al., School Exemption Data and Geocoding as Tools for Assessing Relationships of Pertussis Clusters to High Immunization Exemption Rates, http://cdc.confex.com/cdc/nic2002/recordingredirect.cgi/id/1446; Public Health Skepticism, 30 ноября 2002 г., http://medpundit.blogspot.com/2002_11_24_medpundit_archive.html
