Property:Query format
From semantic-mediawiki.org
"Query format" is a predefined property that holds the name of the result format used in a query and is provided by Semantic MediaWiki. This property is pre-deployed (also known as special property) and comes with additional administrative privileges but can be used just like any other user-defined property.
This is the page of special property Query format. It lists all pages using this special property. See the help page Special property "Query format" for further information.