Acapulco photographs, 1934 Box 2 Series I: Personal papers and photos, 1831-2005, undated, bulk 1933-1979Subseries I.4: Mexico, 1933-1935
Aldriches of "Rokeby" letters, 1944-1960 Box 1 Series I: Personal papers and photos, 1831-2005, undated, bulk 1933-1979Subseries I.2: Correspondence, 1933-1999 undated [Bulk dates: 1933-1980], 1933-1999, undated
Alexander Trachtenberg History of May Day, 1937 Box 11 Series IV: Collected books, 1778-1983, bulk 1920s-1979Subseries IV.2: Socialist Literature, 1932-1959