Thenu, Novitha Leonora Thedora, et al. “Observation of Changes in Acoustic Emission and Vibration Signals to Transverse Crack on Rotating Shaft: An Experiment Investigation”. International Journal on Advanced Science, Engineering and Information Technology, vol. 7, no. 5, Oct. 2017, pp. 1853-60, doi:10.18517/ijaseit.7.5.1948.