@article{1092136,
  author = {K. Niinuma and M. Kino and A. Doi and K. Hada and H. Nagai and S. Koyama},
  title = {Discovery of a Wandering Radio Jet Base after a Large X-Ray Flare in the Blazar Markarian 421},
  year = {2015},
  journal = {ApJ},
  volume = {807},
  pages = {L14},
  doi = {10.1088/2041-8205/807/1/L14},
  language = {eng},
}