Free Men vs. The Union Closed Shop
The Marriner S. Eccles Document Collection
Extra edition of the Freeman Magazine, featuring an article by Donald R. Richberg.
Richberg, Donald R., 1951, Free Men vs. The Union Closed Shop, from The Marriner S. Eccles Document Collection, accessed May 23, 2013 from FRASER, http://fraser.stlouisfed.org/docs/historical/eccles/030_09_0008.pdf