Robert P. Munafo, 2000 Feb 7.
A theorem of complex dynamics, proven by Fatou and Julia in 1919.
You can determine which it is by iterating from the critical point z=0. This is equivalent to finding out if z is in the Mandelbrot set.
From the Mandelbrot Set Glossary and Encyclopedia, by Robert Munafo, (c) 1987-2017. Mu-ency index
This page was written in the "embarrassingly readable" markup language RHTF, and was last updated on 2017 Feb 02. s.11