1. Letter from Felix Haurowitz to Michael Heidelberger Publication: Produced: 10 February 1948 Subject(s): Allergy and ImmunologyAntigen-Antibody Reactions Archival Collection: The Michael Heidelberger Papers (Profiles in Science)
2. Letter from William C. Boyd, Boston University to Michael Heidelberger Publication: Produced: 10 December 1940 Subject(s): PrecipitinsAgglutinationAntigen-Antibody ReactionsAllergy and Immunology Archival Collection: The Michael Heidelberger Papers (Profiles in Science)