What river has the strongest and largest flow at the mouth of Kattegat?
select ?ent where { ?ent wdt:P31 wd:Q3529419 . ?ent wdt:P2225 ?obj . ?ent wdt:P403 wd:Q131716 } ORDER BY DESC(?obj)LIMIT 5 
small river: Q3529419 kattegat: Q131716