
https://www.bti-project.org/en/data/rankings/status-index/

http://www.express.co.uk/news/uk/840143/DNA-English-villages-foreigners-residents-study

https://www.insightcrime.org/wp-content/uploads/2020/04/El-narcotraficante-invisible-tras-las-huellas-de-Memo-Fantasma_InSight-Crime-Marzo-2020.pdf