Experiment	Measurement	Reference
Belle	\([6.81 \pm 0.23\mbox{ (stat)} \pm 0.72\mbox{ (syst)}] \times 10^{-3}\)	PRD (R)70,111103(2004)
Average	\(\mathbf{[6.81 \pm 0.76\mbox{ (combined)}] \times 10^{-3}}\)