1. Letter from Donald L. D. Caspar to Rosalind Franklin Publication: Produced: 1 November 1954 Subject(s): Tobacco Mosaic VirusX-Ray Diffraction Archival Collection: The Rosalind Franklin Papers (Profiles in Science)
2. Letter from Donald L. D. Caspar to Rosalind Franklin Publication: Produced: 9 April 1955 Subject(s): Tobacco Mosaic VirusX-Ray Diffraction Archival Collection: The Rosalind Franklin Papers (Profiles in Science)
3. Letter from Donald L. D. Caspar to Rosalind Franklin Publication: Produced: [ca. April-May 1955] Subject(s): Tobacco Mosaic VirusX-Ray Diffraction Archival Collection: The Rosalind Franklin Papers (Profiles in Science)
4. Letter from Donald L. D. Caspar to Rosalind Franklin Publication: Produced: [1956] Subject(s): Tobacco Mosaic VirusRNA Archival Collection: The Rosalind Franklin Papers (Profiles in Science)
