Article date: Sep 1968
Article title: Counting systems and the relationship between numbers and the real world
Mathematical Games column? Y
Book: 8. Mathematical Magic Show
Chapter: 8. Finger Arithmetic
This data confirmed? yes
Notes
Peter Rowlett (27 August 2022):
Peter Rowlett initial guess (Very uncertain)
Peter Rowlett (30 October 2023):
I have seen this chapter and column side-by-side and they match.