Journal of Physics A: Mathematical and General.
Vol. 24.
1991.
P. 2731-2741
Summary: "It is shown, for the self-consistent system of scalar, electromagnetic and gravitational fields in general relativity, that the equations of motion admit a special kind of solution with spherical or cylindrical symmetry. For these solutions, the physical fields vanish and the space-time is flat outside of the critical sphere or cylinder. Therefore the mass and the electric charge of any of of these configurations are zero."