Titles
- Letter from A. J. Riker to Joshua Lederberg1
- Letter from A. K. Bhattacharyya to Joshua Lederberg2
- Letter from A. Klopstock to Joshua Lederberg1
- Letter from A. Lima-de-Faria to Joshua Lederberg1
- Letter from A. M. Stewart to John W. Gofman1
- Letter from A. R. Gopal-Ayengar to Joshua Lederberg2
- Letter from A. T. Ganesan to Joshua and Esther Lederberg7
- Letter from A. T. Wilson to Joshua Lederberg1
- Letter from Aaron Cohodes, Instructional Dynamics Incorporated to Joshua Lederberg2
- Letter from Aaron J. Teller to Joshua Lederberg1
- Letter from Aaron Klug to Francis Crick1
- Letter from Aaron Novick to Bruce Stocker1
- Letter from Aaron Novick to Hugh Odishaw1
- Letter from Aaron Novick to Joshua Lederberg7
- Letter from Adrian Kantrowitz to Doris J. W. E. Escher1
- Letter from Adrian Kantrowitz to Helen B. Taussig1
- Letter from Adrian Kantrowitz to Jack A. Cannon1
- Letter from Adrian Kantrowitz to Luther L. Terry1
- Letter from Adrian Kantrowitz to Nelson H. Kraeft1
- Letter from Adrian Kantrowitz to R. C. Bunts1