Question: Show me the book that Muhammad Ali wrote.
SPARQL query:
PREFIX onto: <http://dbpedia.org/ontology/> 
PREFIX res: <http://dbpedia.org/resource/> 
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> 
SELECT DISTINCT ?uri 
WHERE { 
         ?uri rdf:type onto:Book . 
         ?uri onto:author res:Muhammad_Ali . 
}