Oracle table lock, unlock

Query which tables are locked
select b.owner,b.object_name,a.session_id,a.locked_mode from v$locked_object a,dba_objects b where b.object_id = a.object_id;

Which session caused the query;
select b.username,b.sid,b.serial#,logon_time from  v$locked_object a,v$session b where a.session_id = b.sid order by b.logon_time;

kill related processes;
alter system kill session '507,96'
507（SID），96（SERIAL）