• Association
• AuditableEvent
• Classification
• ClassificationScheme
• Concept
• EmailAddress
• ExtensibleObject
• ExternalIdentifier
• ExternalLink
• ExtrinsicObject
• InternationalString
• Key
• LocalizedString
• Organization
• PersonName
• PostalAddress
• RegistryEntry
• RegistryObject
• RegistryPackage
• Service
• ServiceBinding
• Slot
• SpecificationLink
• TelephoneNumber
• URIValidator
• User
• Versionable