Some additional reading material would be:
"Hydraulic Component Design and Selection" Dr. Fitch and Dr. Hong
"Hydraulic System Assurance" Dr. Fitch and Dr. Hong
"Fluid Contamination Control" Dr. Fitch
But if you want the original text regarding hydraulics, which originated from MIT, check out
"Fluid Power Control" by John F. Blackburn, Grehard Reethof, and J. Lowen Shearer.
Those three names above are the grandfathers of modern hydraulic analysis and study.
I believe from there, one when to Penn State, the other to Raytheon and I think...but may be wrong...one stayed at MIT. Dr. Fitch would be a second generation hydraulicist and Dr. Hong the third in this line.
The three from MIT, were the original commissioned engineers to begin hydraulic research after WW2.
Additionally, I have heard, but not have had time to read, that the following book was designed to be a follow up for Fluid Power Control
"Hydraulic Control Systems" Herbert Eugene Merritt