PREFIX cito: <http://purl.org/spar/cito/>

PREFIX dcterms: <http://purl.org/dc/terms/>

PREFIX datacite: <http://purl.org/spar/datacite/>

PREFIX literal: <http://www.essepuntato.it/2010/06/literalreification/>

PREFIX biro: <http://purl.org/spar/biro/>

PREFIX frbr: <http://purl.org/vocab/frbr/core#>

PREFIX c4o: <http://purl.org/spar/c4o/>

SELECT ?cited ?cited_ref ?title ?url WHERE {

    <https://w3id.org/oc/ccc/br/070444> cito:cites ?cited .

    OPTIONAL { 

        <https://w3id.org/oc/ccc/br/070444> frbr:part ?ref .

        ?ref biro:references ?cited ;

            c4o:hasContent ?cited_ref 

    }

    OPTIONAL { ?cited dcterms:title ?title }

    OPTIONAL {

        ?cited datacite:hasIdentifier [

            datacite:usesIdentifierScheme datacite:url ;

            literal:hasLiteralValue ?url

        ]

    }

}