Noskievič, P. ., and M. A. L. . De León. “Control of the Test Rig for Spring Stiffness Measurement With Hydraulic Integrated Actuator and Computer Vision”. International Journal of Fluid Power, vol. 21, no. 3, Feb. 2021, pp. 305-26, doi:10.13052/ijfp1439-9776.2131.