Subclass Subgroup Patent
F03B 7/00 09810193
  13/10 09810194
  13/142 09810195
  15/00 09810196
F03D 1/003 09810197
  1/0675 09810198
  7/0264 09810199
  7/04 09810200
  9/32 09810201
  11/00 09810202
  11/0091 09810203
  13/25 09810204