1. Department of Homeland Security.Population estimates: illegal alien population residing in the United States: January 2015.https://www.dhs.gov/sites/default/files/publications/18_1214_PLCY_pops-est-report.pdf. December 2018. Accessed January 2019.
2. Pew Research Center. U.S. unauthorized immigrant population estimates by state 2016.http://www.pewhispanic.org/interactives/u-s-unauthorized-immigrants-by-state/. Published February 5 2019.
3. European Commission.Annexes to the communication from the commission to the European Parliament the Eurpoean Council and the Council: progress report on the Implementation of the European Agenda on Migration.https://ec.europa.eu/home-affairs/sites/homeaffairs/files/what-we-do/policies/european-agenda-migration/20180516_annexes_progress-report-european-agenda-migration_en.pdf. Published May 16 2018.
4. To Amend the Public Health Service Act to Establish a Preference in the Allocation of Donated Organs for Individuals who Are Lawfully Present in the United States and for Other Purposes. HR 5518 115th Cong (2018).https://www.congress.gov/bill/115th-congress/house-bill/5518/text.
5. Organ and Tissue Transplantation: Uninsured or Undocumented Individuals. AB 2846 (Ca2018).https://leginfo.legislature.ca.gov/faces/billTextClient.xhtml?bill_id=201720180AB2846.