RT Article T1 Policy Essay: A systematic approach to precursor behaviors JF Criminology & public policy VO 8 IS 3 SP 607 OP 621 A1 Wigle, John LA English YR 2009 UL https://krimdok.uni-tuebingen.de/Record/1912654962 DO 10.1111/j.1745-9133.2009.00577.x