Q2152

{"type":"item","id":"Q2152","labels":{"en":{"language":"en","value":"used as reference constraint"}},"descriptions":{"en":{"language":"en","value":"type of constraint for Gratisdata properties: used to specify that a property must only be used in references or instances of citation"}},"aliases":{"en":[{"language":"en","value":"source-only constraint"},{"language":"en","value":"reference-only constraint"}]},"claims":[],"sitelinks":[]}