diff --git a/sex/sex_work.md b/sex/sex_work.md
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--- a/sex/sex_work.md
+++ b/sex/sex_work.md
@@ -16,3 +16,8 @@
 > *“Those of us who work on the street are running from the police, pushed into more isolated areas because clients are **fearful of arrest**”*
  
  ~ Niki Adams of the English Collective of Prostitutes
+ 
+ * [Bisschop et al. 17](https://www.aeaweb.org/articles?id=10.1257/pol.20150299) [(pdf)](https://pubs.aeaweb.org/doi/pdfplus/10.1257/pol.20150299)
+   * Study of street prostitution in 25 Dutch cities between 1994-2011 shows that "safe prostitution zones" (tipplezones) decrease instances of sexual abuse and other forms of criminal activity.
+   * *"Opening a tippelzone decreases registered sexual abuse and rape by about 30-40 percent in the first two years.*"
+   * *"For cities which enforced licensing in tippelzones, we also find reductions in drug-related crime and long-term effects on sexual assaults."*