Description  Claims  Drawing  Cited references 

SU1329966A1   [0002] 
DE19737886C1   [0029] 
EP0993767B1   [0031]  [0070] 
US5709254A   [0038] 
US3870125A   [0043]  [0047] 
GB539956A   [0045] 
SE518366C2   [0049]