1. Regulations for the sale of viruses, serums, toxins, and analogous products in the District of Columbia and in interstate traffic Author(s): United States. Public Health Service. Publication: Washington [D.C.] : U.S. Government Printing Office, 1941 Subject(s): VirusesVaccinesAntitoxinsToxins, BiologicalUnited States
2. Letter from Colin M. MacLeod to Michael Heidelberger Publication: Produced: 20 May 1941 Subject(s): VaccinesPolysaccharidesPneumococcal Infections Archival Collection: The Michael Heidelberger Papers (Profiles in Science)