For static, purely electric configurations the twist potential and the magnetic potential vanish. The ansatz (7.12), together with the definitions of the Ernst potentials, and (see Section 6.4), yields[262, 220], with spacetime metric and electric potential . The MP metric describes a regular black-hole spacetime, where the horizon comprises disconnected components. Hartle and Hawking  have shown that all singularities are “hidden” behind these null surfaces. In Newtonian terms, the configuration corresponds to arbitrarily-located singularities are “hidden” behind these null surfaces. In Newtonian terms, the configuration corresponds to arbitrarily-located charged mass points with .
Non-static members of the Israel–Wilson–Perjés class were constructed as well [179, 267]. However, these generalizations of the MP multi–black-hole solutions share certain unpleasant properties with NUT spacetime  (see also [32, 237]). In fact, the results of  (see [139, 78, 154] for previous results) suggest that – except the MP solutions – all configurations obtained by the Israel–Wilson–Perjés technique either fail to be asymptotically flat or have naked singularities.
Living Rev. Relativity 15, (2012), 7
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