Experiment	Measurement	Reference
BaBar	\([4.00 \pm 0.61\mbox{ (stat)} \pm 0.61\mbox{ (syst)}] \times 10^{-4}\)	PRD 74 (2006) 031103
Average	\(\mathbf{[4.00 \pm 0.86\mbox{ (combined)}] \times 10^{-4}}\)