Article date: Jul 1968
Article title: On the meaning of randomness and some ways of achieving it
Mathematical Games column? Y
Book: 7. Mathematical Carnival
Chapter: 13. Random Numbers
This data confirmed? yes
Notes
Peter Rowlett (27 August 2022):
Peter Rowlett initial guess (Very uncertain) Book copyright info says this is from 1965, 1966 or 1967, but this title seems most likely. Definitely uncertain.
Peter Rowlett (29 October 2023):
I have seen this chapter and column side-by-side and they match (despite the date mismatch noted above!).