1. Letter from Joshua Lederberg to Allen G. Marr Publication: Produced: 15 September 1952 Subject(s): Equipment and SuppliesIndicators and Reagents Archival Collection: The Joshua Lederberg Papers (Profiles in Science)
2. 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)