Retrieves a list of users referenced by a trusted service. Clients cannot construct the URL themselves. The correct URL will be provided in the HAL links of another API response, in the _links object with a key like ref:users:0.
The list of comma-separated user IDs generated by a trusted service.
The signature of this request generated by a trusted service.
OK
A map of referenced users indexed by the user ID.
The referenced user, or null if it no longer exists.