42. The Theory of Inter-allelic Complementation Creator: Orgel, Leslie E.Crick, Francis, 1916-2004 Date: 1964 Publisher: London Academic Press Genre: ArticlesLetters (correspondence)
43. Molecular Genetics: The Ideas Creator: Crick, Francis, 1916-2004 Date: [January 1964] Genre: Lecture notes
44. Letter from Francis Crick to Harold Frank Robinson, North Carolina State University Institute of Biological Sciences Creator: Crick, Francis, 1916-2004 Date: 21 February 1964 Genre: Letters (correspondence)
45. Letter from Francis Crick to Carl C. Lindegren Creator: Crick, Francis, 1916-2004 Date: 3 July 1964 Genre: Letters (correspondence)
46. Letter from Francis Crick to Warren Weaver Creator: Crick, Francis, 1916-2004 Date: 6 July 1964 Genre: Letters (correspondence)
47. Letter from Francis Crick to Leonard S. Lerman Creator: Crick, Francis, 1916-2004 Date: 6 November 1964 Genre: Letters (correspondence)
48. General Nature of the Genetic Code Creator: Crick, Francis, 1916-2004 Date: 1965 Publisher: The Robert A. Welch Foundation Offices Genre: Articles
49. Letter from Francis Crick to Alexander Rich Creator: Crick, Francis, 1916-2004 Date: [7 January 1965] Genre: Letters (correspondence)
50. Letter from Francis Crick to James D. Watson Creator: Crick, Francis, 1916-2004 Date: [7 January 1965] Genre: Letters (correspondence)