https://www.brookings.edu/opinions/the-foreign-policies-of-the-sinaloa-cartel-and-cjng-part-iii-africa/
http://www.ilo.org/wcmsp5/groups/public/—dgreports/—dcomm/—publ/documents/publication/wcms_604882.pdf
https://www.economiesuisse.ch/de/artikel/die-praemien-sind-zu-35-prozent-einkommensabhaengig