Article date: Dec 1972
Article title: Knotty problems with a two-hole torus
Mathematical Games column? Y
Book: 11. Knotted Doughnuts and Other Mathematical Entertainments
Chapter: 5. Doughnuts: Linked and Knotted
This data confirmed? yes
Notes
Peter Rowlett (27 August 2022):
Peter Rowlett initial guess (Uncertain)
Peter Rowlett (1 November 2023):
I have seen this chapter and column side-by-side and they match.