Article date: Dec 1976
Article title: In which "monster" curves force redefinition of the word "curve"
Mathematical Games column? Y
Book: 13. Penrose Tiles to Trapdoor Ciphers
Chapter: 3. Mandelbrot’s Fractals
This data confirmed? yes
Notes
Peter Rowlett (27 August 2022):
Peter Rowlett initial guess (Uncertain)
Peter Rowlett (4 November 2023):
I have seen this chapter and column side-by-side and they match.