Question: What is the subject of the book which preceded Sagan's Cosmos?
SPARQL query: SELECT DISTINCT ?uri WHERE { <http://dbpedia.org/resource/Cosmos_(Carl_Sagan_book)> <http://dbpedia.org/ontology/previousWork> ?x . ?x <http://dbpedia.org/property/subject> ?uri  . }
Answer: The subject of the previous work of Cosmos Carl Sagan book are [Brain, Outline of space science, Intellect, Paul Broca].