2[2]Vael Georges , Achten P A J ,Potma Jeroen.Cylinder control with the floating cup hydraulic transformer[R]. In The Eighth Scandinavian International Conference on Fluid Power, SICFP'03,Tampere, Finland,2003.
3[3]Vael Georges E M, Achten P A J, Fu Zhao. The Innas hydraulic transformer: The key to the hydrostatic common pressure rail[J]. SAE2000-01-2561.
4[4]Achten P A J, Palmberg J O. What a difference a hole makes the commercial value of the Innas hydraulic transformer[R]. In The Sixth Scandinavian International Conference on Fluid Power, SICFP'99, Tampere, Finland:1999.