What 9-Cylinder radial engine model has the least bore?
select ?ent where { ?ent wdt:P31 wd:Q15057021 . ?ent wdt:P2556 ?obj . ?ent wdt:P1002 wd:Q15135215} ORDER BY ASC(?obj)LIMIT 5 
engine model: Q15057021 9-cylinder radial: Q15135215