How to find organization wise subordinates

[khadeer]

select *
FROM per_org_structure_elements pose,
hr_all_organization_units hou1,
hr_all_organization_units hou2,
hr_all_organization_units_tl hou1tl,
hr_all_organization_units_tl hou2tl
WHERE pose.organization_id_parent = hou1.organization_id
AND pose.organization_id_child = hou2.organization_id
AND hou1.organization_id = hou1tl.organization_id
AND hou2.organization_id = hou2tl.organization_id
AND hou1tl.LANGUAGE = USERENV ('LANG')
AND hou2tl.LANGUAGE = USERENV ('LANG')
and hou1.name like 'Pearson - Assessment and Testing'

please help me in avoiding duplicate rows.