Subclass Subgroup Patent
G01R 31/086 12169215
  31/2607 12169216
  31/2808 12169217
  31/2836 12169218
  31/2862 12169219
  31/287 12169220
  31/3016 12169221
  31/31922 12169222
  31/367 12169223
  31/3835 12169224
  31/389 12169225
  31/52 12169226
  31/56 12169227