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                        | (84) | Designated Contracting States: |  
                        |  | AT BE CH DE DK ES FR GB GR IE IT LI LU MC NL PT SE |  
 
                     
                        | (30) | Priority: | 20.02.1997 GB 9703532 12.12.1997 GB 9726401
 
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                        | (71) | Applicant: BTG INTERNATIONAL LIMITED |  
                        |  | London EC4M 7SB (GB) |  
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                        | (72) | Inventors: |  
                        |  | 
                              RICHARDS, Robert, Michael, EdwardAberdeen AB10 1XY (GB)
DURHAM, David, GarnetPeterculterAberdeen AB1 0RL (GB)
LIU, Iain, XiaojunAberdeen AB2 2XU (GB)
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                        | (74) | Representative: England, Christopher David |  
                        |  | BTG International Ltd.,10, Fleet Place,Limeburner Lane London EC4M 7SB
 London EC4M 7SB (GB)
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