What is {headed by} of {Library of Congress}, that has {ethnicity} is {African Americans} ?
Who heads the Library of Congress, who is also of African American ethnicity?
SELECT ?answer WHERE { wd:Q131454 wdt:P488 ?answer . ?answer wdt:P172 wd:Q49085}
SELECT ?answer WHERE { ?statement1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q131454> . ?statement1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P488>. ?statement1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?answer . ?statement2 <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?answer. ?statement2 <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P172> . ?statement2 <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q49085> . }
Who heads the Library of Congress, who is additionally of African American ethnicity?