The Allied Mission to Observe Greek Elections was established when on September 19, 1945 the Governments of Britain, France, and the United States accepted the Greek Government's invitation to send observers for the general elections and plebiscite to be held in 1946. The collection consists of correspondence, circulars, memos, press extracts, and and maps, including one annotated map depicting the locations of headquarters among the country.

Consists of the records (1760-1974) of a large business conglomerate in northern Mexico founded by Pedro R. Prieto and owned by branches of the Prieto family, including Maíz family members, for three generations.

Consists of approximately 701 flat works from the collections of the Princeton University Art Museum, temporarily transferred to the Princeton University Library for use in Princeton University courses during the Spring 2023 semester.

Consists of several hundred print photographs (most are captioned) primarily from various French news outlets and agencies documenting people and events of numerous countries and geographic regions spanning the mid to late 20th century.

The papers comprise documents relating to all periods of the life of Kurt Gödel, foremost mathematical logician of the twentieth century, including scientific correspondence, notebooks, drafts, unpublished manuscripts, academic, legal, and financial records, and all manner of loose notes and memoranda.

Consists of 108 letters by Mencken to Dent Smith between the years 1938 and 1945, with Smith's side of the correspondence present in carbon copies.

Consists of 110 letters by influential magazine editor and critic H. L. Mencken to David Warren Ryder, a San Francisco area journalist, written mainly from Baltimore and New York between the years 1922 and 1947.

William Byler was Executive Director of the Association on American Indian Affairs (AAIA) from 1962 to 1980. After leaving AAIA, Byler continued advocating for the Native American community, first at Gerard, Byler and Associates and later at William Byler Associates. Byler's papers document his work on behalf of the Native American community after leaving AAIA. The papers include legal memoranda, draft and final agreements between Native American communities and companies or government agencies, and court documents, as well as topical files of related legislation and reports on the issues.

Consists of research files, primarily government records, of scholar and author Jacques Roumani (1944-2016) on Libya during the period of Italian colonization.