World Health Organization. Expert Committee on Smallpox. Meeting (1964 : Geneva, Switzerland)2012-06-172012-06-1719631963-12-31Smallpox/WP/6https://iris.who.int/handle/10665/67695Paper presented at the meeting of the Expert Committee on Smallpox, Geneva, 14-20 Janaury 1964Smallpox/WP/614 p.enSmallpoxVaccinationCommunicable Diseases and their ControlInternational certificate of vaccination or revaccination against smallpox / prepared by the SecretariatCertificat international de vaccination ou de révaccination contre la variole / document établi par le SecrétariatPrevention and controlLegislation