1. Letter from W. H. Crichton to D. Gordon Cheyne Publication: Produced: 23 December 1943 Subject(s): Typhus, Epidemic Louse-BorneAttitude of Health PersonnelOrganization and Administration Archival Collection: The Fred L. Soper Papers (Profiles in Science)
2. Letter from W. H. Crichton to D. Gordon Cheyne Publication: Produced: 24 December 1943 Subject(s): Typhus, Epidemic Louse-BorneAttitude of Health PersonnelOrganization and Administration Archival Collection: The Fred L. Soper Papers (Profiles in Science)