Stabilization of superconductivity in spin glass

The difference between the free energies of the superconducting and normal states of a disordered magnetic system in the spin glass phase is calculated. This difference is expanded with respect to the order parameter of the superconducting state near the critical point $T\sim T_{\rm c}$ and a study is made of the behavior of the expansion coefficients $f_1$ and $f_2$ in the region of large concentrations of the magnetic impurity, where re-entrant behavior is observed. It is concluded that at low temperatures the phase transition to the normal state is a transition of the second kind, that the solutions of the equation for the critical temperature of transition of the spin glass to the superconducting state [2] are physical, and that the superconductivity state in the spin glass is stable.