The branching ratio revisited C. Hanhart, S. Holz, B. Kubis, A. Kupść, A. Wirzba and C. W. Xiao Eur. Phys. J. C, 77 2 (2017) 98 Published online: 14 February 2017 DOI: 10.1140/epjc/s10052-017-4651-x