1. Has surveillance been adequate to detect endemic measles in the United States?;Harpaz;J Infect Dis,2004
2. Report of the Seventh Meeting of the Technical Advisory Group on Expanded Program on Immunizations and Polio Eradication, Cartagena, Columbia, 11–14 July 1989;Pan American Health Organization
3. Eradication of wild poliovirus from the Americas: acute flaccid paralysis surveillance, 1988–1995;De Quadros;J Infect Dis,1997
4. The surveillance challenge: final stages of eradication of poliomyelitis in the Americas;Andrus;MMWR Morb Mortal Wkly Rep,1992
5. Strategies for the certification of the eradication of wild poliovirus transmission in the Americas;Pan American Health Organization;Bull Pan Am Health Organ,1993