https://home.treasury.gov/system/files/136/Treasury_Study_WoA.pdf
http://wir2018.wid.world/files/download/wir2018-summary-spanish.pdf
https://insightcrime.org/wp-content/uploads/2023/05/The-Flow-of-Precursor-Chemicals-for-Synthetic-Drug-Production-in-Mexico-InSight-Crime-March-2023-3.pdf
https://www.fawcettsociety.org.uk/Handlers/Download.ashx?IDMF=bb90467f-174b-4f68-801a-4ae04e4fd33c