Technical data for this type of fractal : click here.

For the factal here :
fn1 = ident(), fn2 = ident(), fn3 = ident(), fn4 = flip()
real(p1) = 2, imag(p1) = 1, real(p2) = 1, imag(p2) = 1, real(p3) = 0, imag(p3) = 1

Note.
The flip function swaps the real and imaginery components
of the complex number, e.g. (4,5) becomes (5,4).