https://theconversation.com/que-factores-explican-la-hiperinflacion-venezolana-216135
https://reformscotland.com/wp-content/uploads/2018/04/The-VAT-opportunity.pdf
http://invs.santepubliquefrance.fr/publications/etat_sante_2017/ESP2017_Ouvrage_complet_vdef.pdf