The next challenge to the dominance of craft unions within the AFL came from inside, as John L. Lewis of the Mine Workers, David Dubinsky of the ILGWU, Sidney Hillman of the Amalgamated Clothing Workers of America, Charles Howard of the International Typographical Union, Thomas McMahon, head of the United Textile Workers, John Sheridan of the Mine, Mill and Smelter Workers Union (the descendant of the WFM), Harvey Fremming from the Oil Workers Union and Max Zaritsky of the Hatters, Cap and Millinery Workers joined to form a Committee for Industrial Organizing within the AFL.