Zhongmin Wang and  Wudong Fan and  Hengshan Zhang and  Yimin Zhou,  Remaining Useful Life Estimation of Bearings Based on Nonlinear Dimensional Reduction Combined with Timing Signals.   journal   = {International Journal of Electronics and Communication Engineering}, [online]. World Academy of Science, Engineering and Technology.
    June 2019, vol. 151(7). 484 - 491
    [viewed 16 November 2019]. Available from: https://publications.waset.org/pdf/10010577.