http://purl.org/dc/terms/format

used by 13:

• ciard-ring
• event-media
• ghent-university-academic-bibliography
• gutenberg
• hebis-bibliographic-resources
• iso-3166-2-data
• legislation-openuplabs
• linked-open-ipa
• opencorporates
• rkb-explorer-webconf
• rkb-explorer-webscience
• southampton-ac-uk-photos
• uk-legislation-api