Yellow page Mobile has attached itself without permission on Google review page. I did not sign-up w
@Mae W The form was an answer to @Richard R not your question.Google shows reviews from around the web in your knowledge panel as @James mentioned as a matter of design. It will show for any 3rd party site uses rich snippet reviews and that shows up in the first 12 results for a brand search.
Here are some articles to help you understand what Google is doing