PREFIX dcat: <http://www.w3.org/ns/dcat#>
PREFIX dc: <http://purl.org/dc/elements/1.1/>
PREFIX vcard: <http://www.w3.org/2006/vcard/ns#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
{
  ?dataset rdf:type dcat:Dataset .
  ?dataset dcat:contactPoint ?contact .
  ?contact vcard:fn ?name. 
  OPTIONAL{
    ?contact vcard:hasEmail ?email .
  }
}