2013:

      Tomonori Totani, Publications of the Astronomical Society of Japan, Vol.65, No.5, pp. 4, (2013).

      ​Kazumi Kashiyama, Kunihito Ioka, and Peter Mesz ´ aros, The Astrophysical Journal Letters, Volume 776, Issue 2, pp. 4, (2013).

      D. Thornton, B. Stappers, M. Bailes et al., Science, Volume 341, Issue 6141, pp. 53-56, (2013).