00685nam 2200169z- 450 9910712652303321(CKB)5470000002495639(EXLCZ)99547000000249563920230509c2019uuuu -u- -engProtecting America's schools : a U.S. Secret Service analysis of targeted school violenceU.S. Department of Homeland Security, United States Secret Service, National Threat Assessment CenterWashington, D.CProtecting America's schools BOOK9910712652303321Protecting America's schools : a U.S. Secret Service analysis of targeted school violence3345987UNINA