“…The techniques employed to address the problems of identity privacy and location privacy overlap with the techniques of anonymous authentication, charging unlinkability, and privacy-preserving billing and payment, and as do the references. The reason is that these papers [41,42,43,44,45,35,34,49,50,51,52,62,63] all hide an EV's real ID, though, based on different techniques, thus providing anonymity and unlinkability. Moreover, location privacy problem is indirectly solved by hiding the IDs in the papers [41,42,43,44,45,35,34,49,50,51,52,62,63].…”