PREFIX rdf:   <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX bench: <http://localhost/vocabulary/bench/>
PREFIX swrc:  <http://swrc.ontoware.org/ontology#>

SELECT ?article
WHERE {
  ?article rdf:type bench:Article .
  ?article ?property ?value
  FILTER (?property=swrc:month)
}