1. Letter from Harold Varmus to Robert A. Weinberg, Massachusetts Institute of Technology Publication: Produced: 17 June 1983 Subject(s): Clone CellsPlasmidsIndicators and Reagents Archival Collection: The Harold Varmus Papers (Profiles in Science)
2. Letter from Harold Varmus to Mike Fried, Imperial Cancer Research Fund Laboratories Publication: Produced: 11 July 1977 Subject(s): Mammary Tumor Virus, MouseAvian Sarcoma VirusesRNA, ViralClone Cells Archival Collection: The Harold Varmus Papers (Profiles in Science)