RT Article T1 Effects of enforcement on illegal markets: Evidence from migrant smuggling along the southwestern border JF Journal of public economics VO 92 IS 10-11 SP 1926 OP 1941 A1 Gathmann, Christina LA English YR 2008 UL https://krimdok.uni-tuebingen.de/Record/1912531100 DO 10.1016/j.jpubeco.2008.04.006