Question: Give me drug references of drugs targeting Prothrombin.
SPARQL:
SELECT DISTINCT ?v0
WHERE { 
        <http://www4.wiwiss.fu-berlin.de/drugbank/resource/targets/3579> <http://www4.wiwiss.fu-berlin.de/drugbank/resource/drugbank/drugReference> ?v0. 
        ?v1 <http://www4.wiwiss.fu-berlin.de/drugbank/resource/drugbank/target> <http://www4.wiwiss.fu-berlin.de/drugbank/resource/targets/3579>. 
}