Experiment	Measurement	Reference
BaBar	\([6.41 \pm 0.36\mbox{ (stat)} \pm 0.39\mbox{ (syst)}] \times 10^{-3}\)	PRD 83, 032004 (2011)
Average	\(\mathbf{[6.41 \pm 0.53\mbox{ (combined)}] \times 10^{-3}}\)