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2. Face gear surface durability investigations;Lewicki;J. Am. Helicopter Soc.,2008
3. Torque splitting by a concentric face gear transmission;Filler,2002
4. Face gearing with a conical involute pinion part 1. the conical involute gear–definition, geometry and generation;Tan,2002
5. Face gearing with a conical involute pinion part 2. the face gear–meshing with the pinion, tooth geometry and generation;Tan,2003