Using tools of effective research look for books in Vassar and Connect NY catalogs.  Subject Headings can guide you to primary sources; these keywords are Library of Congress Subject Heading vocabulary indicating primary sources:

sources, letters, interviews, speeches, personal narratives, diaries, correspondence, sermons, notebooks, sketches, description and travel, treaties, pamphlets, biography (includes memoirs), newspapers, periodicals, pictorial works, art, architecture, portraits, caricatures and cartoons, cookery, decorative arts, furniture, material culture, guide books, maps, fiction, poetry, periodicals, newspapers, bibliography, early works to 1800

Not every primary source includes one of these words, but it's a great start.  For example:

CRL collection can be requested through InterLibrary Loan.  Indicate the OCLC# for any item you request.

CRL's collection specializes in foreign and ethnic newspapers, as well as microfilm collections of archival collections.