Hanh-Phuc Le, Michael D. Seeman, Seth Sanders, Visvesh S. Sathe, Samuel Naffziger, Elad Alon. 2 at 81% efficiency. In IEEE International Solid-State Circuits Conference, ISSCC 2010, Digest of Technical Papers, San Francisco, CA, USA, 7-11 February, 2010. pages 210-211, IEEE, 2010. [doi]
Abstract is missing.