1. Poliomyelitis;World Health Organization,2014
2. Update on vaccine-derived polioviruses – worldwide, July 2012–December 2013;Diop;MMWR Morb Mortal Wkly Rep,2014
3. A war within a war;Roberts;Science,2014
4. Virus excretion after mass vaccination with attenuated polioviruses in Hungary;Domok;Br Med J,1961
5. Oral poliovirus vaccine in tropical Africa: greater impact on incidence of paralytic disease than expected from coverage surveys and seroconversion rates;Heymann;Bull World Health Organ,1987