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 . }
What is the subject of the book which preceded Sagan's Cosmos?
SELECT DISTINCT ?b WHERE { resource:Cosmos_(_Carl_Sagan_book) property:previous_work ?q . ?q property:subject ?b . }
Brain, Outline of space science, Intellect, Paul Broca
The subject of the previous work of Cosmos Carl Sagan book are [Brain, Outline of space science, Intellect, Paul Broca].
The subject of Carl Sagan's previous book is [Brain, The Shape of Space Science, Phelps, Paul Brock].