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https://www.htlgroup.com/general/the-difference-between-pneumatic-hydraulic-and-electrical
[2] Johnston, S. and Johnston, K. (2012) Basics of Clutches, All about Automation.
https://www.allaboutautomation.com
[3] Hidehito, H. (2016) Clutch Knowledge, Exedy Corporation, Japan.
https://www.exedymarket.com/images/english/materials/3._3.jpg
[4] Budynas, R.G. and Nisbett, J.K. (2011) Load and Stress Analysis. Shngley’s Mechanical Engineering Design, 9th Edition, McGraw-Hill Educational Books, New York, 71-146.