2011 report by the Congressional Research Service on expenditures for conflicts and terrorism-related operations since 2001.
2004 paper in the Journal of Strategic Studies on the dynamics of aerial campaigns over Iraq and Bosnia.
2006 study by the University of Colorado, Rutgers and UCLA on the likely effects of a nuclear explosion in a densely populated city.
2010 study by the World Bank and Laval University for the Cairo-based Economic Research Forum on development and economic challenges in the Arab world
2008 paper by researchers from Harvard, MIT and Northwestern University on the potential effect of climate change on nations' economic growth.