Headline: Una dura prueba al sistemaLink: http://www.eluniverso.com/opinion/2017/02/17/nota/6051049/dura-prueba-sistemaPublication Date: Friday, February 17, 2017Primary Source: El Universo (Ecuador)Type: op-edFormat: Newspaper (Print)Nature of Mention: authoredScholar: Calderon, GabrielaResearch Area: Immigration and Labor MarketsSubjects: Donald Trump and immigration