https://www.gov.uk/government/news/covid-19-sales-and-pricing-practices-during-coronavirus-outbreak
https://theconversation.com/dividendos-noticias-financieras-y-sentimientos-un-trio-que-ayuda-a-predecir-el-valor-de-mercado-de-una-empresa-225500
http://voxeu.org/article/crowds-and-constitutions-insights-iceland