Query to check which session is using TEMPORARY Tablepace

select  su.username , ses.sid ,ses.serial# , su.tablespace , ceil((su.blocks * dt.block_size) / 1048576) MB
from v$sort_usage su ,dba_tablespaces dt , v$session ses where   su.tablespace = dt.tablespace_name and su.session_addr = ses.saddr order by MB desc