Jouppila, V. T., Gadsden, S. A., Bone, G. M., Ellman, A. U. and Habibi, S. R. (2018) “Sliding mode control of a pneumatic muscle actuator system with a PWM strategy”, International Journal of Fluid Power, 15(1), pp. 19–31. doi: 10.1080/14399776.2014.893707.