http://publications.europa.eu/webapi/rdf/sparql?
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PREFIX cdm: <http://publications.europa.eu/ontology/cdm#>
SELECT distinct ?OJ ?title_ group_concat(distinct ?author; separator=",") as ?authors ?date_document ?manif_fmx4 ?fmx4_to_download
WHERE 
{
?work a cdm:official-journal.
?work cdm:work_date_document ?date_document.
FILTER(substr(str(?date_document),1,4)='2019')
?work cdm:work_created_by_agent ?author.
?work owl:sameAs ?OJ.
FILTER(regex(str(?OJ),'/oj/'))
OPTIONAL{?exp cdm:expression_title ?title.
?exp cdm:expression_uses_language ?lang.
?exp cdm:expression_belongs_to_work ?work.
FILTER(?lang =<http://publications.europa.eu/resource/authority/language/ENG>)
OPTIONAL{?manif_fmx4 cdm:manifestation_manifests_expression ?exp.
?manif_fmx4 cdm:manifestation_type ?type_fmx4.
FILTER(str(?type_fmx4)='fmx4')}}
BIND(IF(BOUND(?title),?title,'The Official Journal does not exist in that language'@en) as ?title_)
BIND(IF(BOUND(?manif_fmx4),IRI(concat(?manif_fmx4,"/zip")),"") as ?fmx4_to_download)
}order by ?date_document

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The language value is set up in ?lang property.
FILTER(?lang =<http://publications.europa.eu/resource/authority/language/ENG>)
Language values are available in the language table available in the EU Vocabularies website 
(https://op.europa.eu/en/web/eu-vocabularies/at-dataset/-/resource/dataset/language).

YEAR is set up in ?date_document property.