C. Cheung, N. Kilfoyle, J. Valdés, S. Sehgal, and R. S. Chavez "Low-Dimensional Spaces for Relating Sensor Signals with Internal Data Structure in a Propulsion System", Advances in Science, Technology and Engineering Systems Journal, vol. 3, no. 6, pp. 23–32, 2018, doi: 10.25046/aj030602.