"For an integer d, these sets are connectedness loci for the Julia sets built from the same formula. The full cubic connectedness locus has also been studied; here one considers the two-parameter recursion , whose two critical points are the complex square roots of the parameter k. A parameter is in the cubic connectedness locus if both critical points are stable.[1] For general families of holomorphic functions, the boundary of the Mandelbrot set generalizes to the bifurcation locus.[citation needed]
