1. Passel JS, Cohn D. Undocumented immigration now trails legal inflow, reversing decades-long trend. Pew Research Center. 2008. http://pewresearch.org/pubs/978/undocumented-immigration . Accessed 16 May 2009.
2. Passel JS, Cohn D. A portrait of unauthorized immigrants in the U.S. Pew Research Center. 2009. http://pewresearch.org/pubs/1190/portrait-unauthorized-immigrants-states . Accessed 16 May 2009.
3. Valenzuela A, Theodore N, Melendez E, Gonzalez A. On the corner: day labor in the United States. Los Angeles: Author; 2006. http://www.sscnet.ucla.edu/issr/csup/uploaded_files/Natl_DayLabor_On_the_Corner1.pdf . Accessed 12 May 2009.
4. Valenzuela A Jr. Day labor work. Ann Rev Sociol. 2003;29:307–33.
5. Neitzel R, Seixas N. Day labor and safety and health initiative report. University of Washington, Department of Environmental and Occupational Health Sciences; 2005. p. 1–24.