The spiral notebooks are numbered, presumably by Landsberg, and are filled with hand-written notes about John Dos Passos, sometimes from telephone interviews with his contemporaries. The folders include alphabetical files. These were not always in sequence, and separate sets of alphabetical files were kept at various points in Landsberg's career, so multiples can be found in these papers. The alphabetical files include correspondence and research notes and it is not always clear why some material was placed in a particular file; some material may have been misfiled by Landsberg.