A footnote in hep-th/0411238 explains:

"E. Calabi has constructed an explicit Kahler–Einstein metric on del Pezzo 6 – recall that this is the blow–up of $\mathbb{CP}_2$ at 6 points – with a certain symmetric configuration of the 6 blown–up points. The corresponding Sasaki–Einstein metric on #6$(S2 × S3)$ is thus also explicit. This metric has apparently never been published"

What is the explicit form of this metric?