Issue No.09 - September (1979 vol.28)
S.C. Lee , School of Electrical Engineering and Computing Sciences, University of Oklahoma
In 1971 Kinsbury and Rayner, publishing under the title "Digital Filtering Using Logarithmic Arithmetic"  disclosed a sign-plus-logarithm number system, and a means of performing addition through single dimensional lookup using the formula c = b + F(a - b). The system was demonstrated on a computer. In 1975 Swartzlander and Alexopoulos disclosed Kinsbury's logarithmic arithmetic as "The Sign/Logarithm Number System" . In 1977, without knowledge of prior art, we reinvented the wheel a third time, dubbing it "Focus," after the focus of resolution around the zero origin . We wish now to acknowledge Kinsbury and Rayner as the pioneer authors, and also Swartzlander and Alexopoulos as prior to our publication.
S.C. Lee, "Addendum to "The Focus Number System"", IEEE Transactions on Computers, vol.28, no. 9, pp. 693, September 1979, doi:10.1109/TC.1979.1675442