SMS Report to find machines with duplicate serial numbers

SELECT
a.Name0,
a.UserName0,
d.sms_installed_sites0 as 'Site Code',
e.Lasthwscan as 'Last hardware Scan',
repeat.SerialNumber0
FROM
v_GS_COMPUTER_SYSTEM a,v_r_system c,v_RA_System_SMSInstalledSites d,v_GS_WORKSTATION_STATUS e,
v_GS_PC_BIOS b,
(SELECT b.SerialNumber0 FROM v_GS_PC_BIOS b GROUP BY
b.SerialNumber0 HAVING (Count(b.SerialNumber0)>1)) as
repeat
WHERE
b.ResourceID = a.ResourceID
and a.ResourceID=c.resourceid
and b.resourceid=d.resourceid
and b.resourceid=e.resourceid
and b.SerialNumber0 = repeat.SerialNumber0
and (c.client0=1 and c.obsolete0=0 and c.Active0=1)
order by
b.SerialNumber0,
a.Name0,
a.UserName0