Property:Has commentary page
This property of type page serves to be able to track commentary pages back to the page with which they belong. To this end, the original page sets the property to the exact value of the commentary page's page name, and the commentary page then can look up the original page by asking for those pages that have this property set to their own page name.
Furthermore, by means of this semantic property, the commentary page itself has the Commentary page form associated with it, so that clicking the property brings the user to the form (even if the page doesn't exist yet).