Field Test: Canon MP-E 65mm f/2.8 1-5x Macro | Popular Photography
Canon MP-E 65mm f/2.8 1–5x Macro - Wikipedia
Macro photography focusing rails for stacked focus, especially with Nikon macro lenses or Canon 65mm MP-E f2.8 macro lens with 5X enlargement | Digital Photography
Canon MPE-65mm Sample Images August 2010: Canon SLR Lens Talk Forum: Digital Photography Review