Name some local authorities of schools which have a mixed gender education system?
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/ontology/gender> <http://dbpedia.org/resource/Mixed-sex_education> . ?x <http://dbpedia.org/ontology/localAuthority> ?uri  . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/School>}
Mixed-sex_education