How to add an external review if the name of the reviewer is not known and is not specified?

Would it be OK to add a review with just the name of the site as the description? I see examples of this, but the guidelines say "Always include the reviewer's name" and all the examples in the guidelines include the reviewer's name, so I don't know if adding a review with just a site name without the reviewer's name is really OK? What to do if there is no reviewer name? If it's OK to add with just a site name in such cases, can it be mentioned in the guidelines?