Papers presented and discussions held :  first International Conference on Live Poliovirus Vaccines, Washington, D.C., 22-26 June 1959 / 
sponsored by the Pan American Health Organization and the World Health Organization, with the cooperation of the Sister Elizabeth Kenny Foundation. 
 - Washington, DC :  Pan American Sanitary Bureau, Regional Office of the World Health Organization,  1959. 
 - Scientific publication / Pan American Sanitary Bureau ;  no. 44 .
 - Publicaciones cientificas (Washington, D.C.) ;  no. 44. .
<br/><br/> Cover title: Live poliovirus vaccines. 
<br/><br/>Includes bibliographical references. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Poliovirus Vaccine -- congresses--Poliovirus Vaccine -- congresses