72-1322-1 (NPS)

April 22, 1955
Presentation of citations by DDE to Dr. Salk and Mr. O'Connor

72-1322-2 (NPS)

April 22, 1955
Presentation of citation by DDE to Dr. Salk and Mr. O'Connor

72-1322-4 (NPS)

April 22, 1955
Dr. Jonas Salk, discoverer of the polio vaccine