How to Appeal, Single Review
We have tried to make the first step in the appeal process quite easy. In the ReviewsInbox™ detail pane next to the review stars you will see an ellipsis. You can select this and the option to appeal will appear as "Flag as inappropriate".
Clicking on this flag will trigger a new browser window hosted directly by Google. The page presents a short form to report a policy violation so that the review is removed.
Simply select the primary reason, supply your email, click the box to confirm you are actually a person (and not a bot), and submit. You will receive an acknowledgement from Google that the request as been submitted.
If the content of the single review contains a direct and flagrant violation of Google's rules, this first step might be all that's necessary to have the review removed.