1. An Ace For You Mr. President;Bristol papers, in possession of the author,1934
2. Autor David . 2017. Quoted in Louis Anslow, “Taxing Robots Was Suggested in the 1940s. It Was a Bad Idea Then, but Things Have Changed.” Timeline. May18. timeline.com/taxing-robots-1940s-productivity-7ba8e0a17332.
3. Belfer Nathan . 1946. Technical Change and Technological Unemployment. PhD diss., Harvard University.