If a person has written a negative review of your website or blog and the article is untrue or has false statements you can issue a TOC. This is a takedown order that you can send to the owner of the site. Your best bet is to send the person an email and try to work this out. You might end up having to hire a lawyer, in the end, to help fight this. Today, there are many sites online that are there to help you and tell you how to handle this problem in a professional way. Don't go on your site and write up a negative blog post about this other website. In the end, you'll both have many problems to sort out. it is best to handle this the correct way and follow the advice of experts online. They are there to help you out and tell or teach you how to take care of this and have the article removed.