Burks, Arthur Walter; Warren, Don W.; Wright, Jesse B. (1954). "An Analysis of a Logical Machine Using Parenthesis-Free Notation". Mathematical Tables and Other Aids to Computation. 8 (46): 53. DOI:10.2307/2001990. JSTOR2001990.
Burks, Arthur Walter; Warren, Don W.; Wright, Jesse B. (1954). "An Analysis of a Logical Machine Using Parenthesis-Free Notation". Mathematical Tables and Other Aids to Computation. 8 (46): 53. DOI:10.2307/2001990. JSTOR2001990.