Experiment	Measurement	Reference
Belle	\([6.8 \pm 1.0\mbox{ (stat)} \pm 0.7\mbox{ (syst)}] \times 10^{-4}\)	PRL 111 (2013) 032001
Average	\(\mathbf{[6.8 \pm 1.2\mbox{ (combined)}] \times 10^{-4}}\)