- Air pilots -- Correspondence
- Lowell, Robert, 1917-1977 -- Correspondence
- Child, Julia -- Correspondence
- DeVoto, Avis -- Correspondence
- Soldiers -- United States -- Correspondence -- Juvenile literature
- Pym, Barbara -- Correspondence
- Businesspeople -- United States -- Correspondence
- Huxley, Juliette, 1896-1994 -- Correspondence
- Thompson, Hunter S. -- Correspondence
- Political prisoners -- South Africa -- Correspondence
- Cooks -- United States -- Correspondence
- Kennedy, Joseph P., Joseph Patrick, 1888-1969 -- Correspondence
- Schlesinger, Bernard, 1896-1984 -- Correspondence
- Children -- Poland -- Correspondence -- Juvenile literature
- Presidents -- South Africa -- Correspondence
- Married people -- United States -- Correspondence
- Painters -- Netherlands -- Correspondence -- Juvenile literature
- McClellan, George B., George Brinton, 1826-1885 -- Correspondence
- Children -- United States -- Correspondence
- Galilei, Galileo, 1564-1642 -- Correspondence
- Lennon, John, 1940-1980 -- Correspondence -- Drama
- Breed, Clara E. -- Correspondence -- Juvenile literature
- Ambassadors -- United States -- Correspondence
- Lindbergh, Anne Morrow, 1906-2001 -- Correspondence
- Women -- United States -- Correspondence
- Children -- Correspondence
- Einstein, Albert, 1879-1955 -- Correspondence
- Authors, American -- 20th century -- Correspondence
- Presidents -- United States -- Correspondence
- Japanese American children -- Correspondence -- Juvenile literature
- Gogh, Theo van, 1857-1891 -- Correspondence -- Juvenile literature
- Country musicians -- Correspondence
- Women pioneers -- West (U.S.) -- Correspondence
- Schlesinger, Winifred, 1897-1986 -- Correspondence
- Knausgård, Karl Ove, 1968- -- Correspondence
- Reagan, Ronald -- Correspondence
- Sarton, May, 1912-1995 -- Correspondence
- Hammett, Dashiell, 1894-1961 -- Correspondence
- Grant, Ulysses S., Ulysses Simpson, 1822-1885 -- Correspondence
- Presidents' spouses -- United States -- Correspondence
- Authors's spouses -- United States -- Correspondence
- Poets, American -- 20th century -- Correspondence
- Diplomats -- Europe -- Correspondence
- Fitzgerald, Zelda, 1900-1948 -- Correspondence
- Children -- Ireland -- Correspondence -- Juvenile literature
- Women authors, American -- 20th century -- Correspondence
- Mothers and sons -- United States -- Correspondence
- Vanderbilt, Gloria, 1924-2019 -- Correspondence
- Politicians -- United States -- Correspondence
- Soldiers -- United States -- Correspondence