1. Harris School of Public Policy Studies, University of Chicago, Chicago, IL, USA
2. Department of Economics, Rider University, Lawrenceville, NJ, USA
3. National Bureau of Economic Research, New York, NY, USA
4. Department of Economics, Bentley University, Waltham, MA, USA
5. Donald E. Stokes Library, Princeton University, Princeton, NJ, USA
6. Department of Pediatrics, Rutgers University–Robert Wood Johnson Medical School, New Brunswick, NJ, USA