1. The EMF 32 Steering Committee, 1200 Pennsylvania Avenue NW, Washington, DC 20460, USA
2. U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue NW, Washington, DC 20460, USA
3. Brookings Institution, 1775 Massachusetts Ave, NW Washington, DC 20036, USA
4. Department of Management Science and Engineering, Stanford University, Huang Engineering Center, 475 Via Ortega, Stanford, CA 94305-4121, USA