Yu, Y.-Z., Peng, B., Liu, K., Zhang, C., Wang, L., Kou, F., et al. (2019). FAST ultra-wideband observation of abnormal emission-shift events of PSR B0919+06. Science China Physics, Mechanics, and Astronomy, 62(5): 959504, pp. 959504. doi:10.1007/s11433-018-9358-8.