[xsl] Removing Duplicate Nodes

[Ashutosh Bhardwaj <ashubhardwaj@xxxxxxxxxx>]

In the xml given below I need to get first 8 unique values for first 
element of docvector field , like (mutual fund, paul murray):
<?xml version="1.0" encoding="utf-8" ?>
<SEGMENTS>

- <SEGMENT NAME="webcluster">

- <RESULTPAGE>

- <RESULTSET FIRSTHIT="1" LASTHIT="25" HITS="25" TOTALHITS="4353" 
MAXRANK="3019" TIME="0.2233">

- <HIT NO="1" RANK="2604" SITEID="0" MOREHITS="0">

 <FIELD NAME="rank">2604</FIELD>

  <FIELD NAME="docvector">[mutual fund, 1][fund sponsored, 
0.953463][practice guidelines, 0.852803]</FIELD>

 </HIT>

- <HIT NO="2" RANK="2293" SITEID="0" MOREHITS="0">

 <FIELD NAME="rank">2293</FIELD>
 <FIELD NAME="docvector">[mutual fund, 1][mutual fund, 
0.816497][positions library, 0.57735]</FIELD>

 </HIT>

- <HIT NO="3" RANK="2292" SITEID="0" MOREHITS="0">

 <FIELD NAME="rank">2292</FIELD>

 <FIELD NAME="docvector">[paul murray, 1][mutual fund, 0.786796][lauren 
hanlon, 0.690066]</FIELD>

 </HIT>

- </RESULTSET>

- <PAGENAVIGATION>

 <NEXTPAGE FIRSTHIT="26" LASTHIT="50" URL="" />

 </PAGENAVIGATION>

 </RESULTPAGE>

 </SEGMENT>

 </SEGMENTS>

Can anybody suggest a way-out?
Thanks,
ashutosh