1. P. M. Fenwick "A binary representation for decimal numbers" Australian Computer Journal4#4 146-149 (November 1972). P. M. Fenwick "A binary representation for decimal numbers" Australian Computer Journal4#4 146-149 (November 1972).
2. J. B. Simpson Simpsons Contemporary Quotations (Houghton Mifflin 1988). J. B. Simpson Simpsons Contemporary Quotations (Houghton Mifflin 1988).
3. J. G. Kemeny T. E. Kurtz Basic programming (Wiley 2nd Ed. 1971). J. G. Kemeny T. E. Kurtz Basic programming (Wiley 2nd Ed. 1971).
4. B. Higman A comparative study of programming languages (Macdonald; American Elsevier 1967) p 102. B. Higman A comparative study of programming languages (Macdonald; American Elsevier 1967) p 102.