1. An information algebra
2. Iverson K. E. A Programming Language. John Wiley & Sons New York 1962. Iverson K. E. A Programming Language. John Wiley & Sons New York 1962.
3. Halstead M. H. Machine-Independent Computer Programming Spartan Books Washington D.C. 1962. Halstead M. H. Machine-Independent Computer Programming Spartan Books Washington D.C. 1962.