Publisher
- Lewis, John F.1
- Lewt Records1
- Lil' Joe Records1
- Literature Bureau of the Workers' International Industrial Union1
- Literature Department, Workers Party of America1
- Longview Museum and Art Center1
- Luther News Agency1
- M. Macdonald & Co. Steeplejacks Limited1
- MD Modern (Houston, Texas)1
- Maier Museum of Art (Lynchburg, Virginia)1
- Marianne Friedland Gallery (Toronto, Canada)1
- Marion Koogler McNay Art Museum1
- Martin News Agency1
- Masonic Quarterly (Newspaper)1
- Massachusetts Social and Economic Opportunity Council1
- McLean, T.1
- McQueen, J. W.1
- Meredith Long Contemporary (Gallery)1
- Milwaukee Corrugating Company. Art Metal Ceiling Department1
- Mitchell, Edward H.1