M. Greenberg, T. Altiok, N. Fefferman, P. Georgopoulos, C. Lacy, M. Lahr, P. Lioy, K. Lowrie, H. Mayer, B. Ozbas, and F. Roberts, A Set of Blended Risk-Based Decision Support Tools for Protecting Passenger Rail-Centered Transit Corridors Against Cascading Impacts of Terrorist Attack DHS March 2011, to be published by Journal of Homeland Security. Posted on website of the Homeland Security Studies and Analysis Institute,  or on HSI website.