D. Phil. Oxford University, 1962
Workingman in American Life (1968).
Labor and the Left, a Study of Socialist and Radical Influences in the American Labor Movement, 1881-1924 (1970).
Failure of a Dream? Essays in the History of American Socialism (1974), (1984), joint author.
Nature's Noblemen: The Fortunes of the Independent Collier in Scotland and the American Midwest, 1855-1889 (1983).
History of the ILGWU in Los Angeles, 1910-1988 (1989), joint author.
"Gender, Class, or Ethno-Cultural Struggle? The Problematic Relationship Between Rose Pesotta and the Los Angeles ILGWU", California History (1993).
The United Mine Workers of America: A Model of Industrial Solidarity? (1996), editor.
United States History: American labor and social movements; U.S., Asian, Black and Mexican immigration; comparative Euro-American history.