Ruhs, Martin, and Bridget Anderson. "Introduction." Who Needs Migrant Workers?: Labour shortages, immigration, and public policy. : Oxford University Press, 2010-08-26. Oxford Scholarship Online. 2011-01-01. Date Accessed 26 May. 2013 <http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199580590.001.0001/acprof-9780199580590-chapter-1>.
Ruhs, M., & Anderson, B.(2010-08-26). Introduction. In Who Needs Migrant Workers?: Labour shortages, immigration, and public policy. : Oxford University Press. Retrieved 26 May. 2013, from http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199580590.001.0001/acprof-9780199580590-chapter-1.
Ruhs, Martin, and Bridget Anderson. "Introduction." In Who Needs Migrant Workers?: Labour shortages, immigration, and public policy. : Oxford University Press, 2010-08-26. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199580590.001.0001/acprof-9780199580590-chapter-1.
Ruhs M, Anderson B. Introduction. In: Ruhs M, Anderson B. Who Needs Migrant Workers?: Labour shortages, immigration, and public policy. Oxford University Press; 2010. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780199580590.001.0001/acprof-9780199580590-chapter-1. Accessed May 26, 2013.