  A nearest-neighbor-interaction Ising spin glass, in the presence of an
external magnetic field, is studied on different hierarchical lattices that
approach the cubic lattice. The magnetic field is considered as uniform, or
random (following either a bimodal or a Gaussian probability distribution). In
all cases, a spin-glass attractor is found, in the plane magnetic field versus
temperature, associated with a low-temperature phase. The physical consequences
of this attractor are discussed, in view of the present scenario of the
spin-glass problem.
