my query is as below

SELECT p.proj_name,o.TRADING_NAME,appl.app_ref_nr,catg.catg_name,
sd.Boys_0_To_5_Sought, sd.BOYS_TO_5_GRANTED,sd.GIRLS_TO_5_GRANTED,r.REGION_NAME, n.NOTE_TEXT
FROM gap_seg_project p,
gap_seg_organisation o,gap_seg_application appl,
gap_seg_category catg,gap_seg_region r,
gap_seg_disability_typ dt,gap_seg_stud_disability sd, gap_seg_appl_notes n, gap_seg_rltd_disability d
WHERE up_gap_seg_sla_doc.up_Total_Amount_Granted(appl.APP_REF_NR)>0
AND r.REGION_ID=appl.REGION_ID
AND o.organisation_id=p.organisation_id
AND catg.CATG_ID=appl.CATG_ID
AND p.proj_id=appl.proj_id
AND appl.APP_REF_NR= n.APP_REF_NR
AND appl.APP_REF_NR=d.APP_REF_NR
AND d.DISABILITY_ID=dt.DISABILITY_ID
AND sd.app_ref_nr = appl.app_ref_nr
AND d.DISABILITY_ID =sd.DISABILITY_ID

here i want to do outer join on gap_seg_stud_disability sd table so i can get data even no match found in gap_seg_stud_disability table.

this syntax gives error
ORA-01417: a table may be outer joined to at most one other table

please give any suggestion to solve this.