161. Letter from Joshua Lederberg to Maxine Singer Creator: Lederberg, Joshua Date: 28 November 1989 Genre: Letters (correspondence)
162. Letter from Maxine Singer to Leon A. Heppel Creator: Singer, Maxine Date: 21 October 1955 Genre: Letters (correspondence)
163. Letter from Leon A. Heppel to Maxine Singer Creator: Cornell UniversityHeppel, Leon A. Date: 5 December 1985 Genre: Letters (correspondence)
164. Letter from Maxine Singer to Horace Freeland Judson Creator: Singer, Maxine Date: 15 August 1995 Genre: Letters (correspondence)
165. Letter from Leon A. Heppel to Maxine Singer Creator: Heppel, Leon A. Date: [13 December 1974] Genre: Letters (correspondence)
166. Letter from Maxine Singer to Leon A. Heppel Creator: Singer, Maxine Date: 6 January 1986 Genre: Letters (correspondence)
167. Letter from Leon A. Heppel to Maxine Singer Creator: Heppel, Leon A.National Institutes of Health (U.S.) Date: 27 October 1955 Genre: Letters (correspondence)
168. Letter from Leon A. Heppel to Maxine Singer Creator: Cornell UniversityHeppel, Leon A. Date: [5 June 1971] Genre: Letters (correspondence)
169. Letter from Leon A. Heppel to Maxine Singer Creator: Cornell UniversityHeppel, Leon A. Date: [3 June 1974] Genre: Letters (correspondence)
170. Letter from Leon A. Heppel to Maxine Singer Creator: Heppel, Leon A. Date: 9 March 1988 Genre: Letters (correspondence)