Merikangas, Kathleen R., and Jules Angst. "Depression and migraine." Migraine: A Spectrum of Ideas. : Oxford University Press, 1990-03-08. Oxford Scholarship Online. 2012-03-22. Date Accessed 25 May. 2013 <http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780192618108.001.0001/acprof-9780192618108-chapter-20>.
Merikangas, K., & Angst, J.(1990-03-08). Depression and migraine. In Migraine: A Spectrum of Ideas. : Oxford University Press. Retrieved 25 May. 2013, from http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780192618108.001.0001/acprof-9780192618108-chapter-20.
Merikangas, Kathleen R., and Jules Angst. "Depression and migraine." In Migraine: A Spectrum of Ideas. : Oxford University Press, 1990-03-08. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780192618108.001.0001/acprof-9780192618108-chapter-20.
Merikangas KR, Angst J. Depression and migraine. In: Sandler M, Collins GM. Migraine: A Spectrum of Ideas. Oxford University Press; 1990. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780192618108.001.0001/acprof-9780192618108-chapter-20. Accessed May 25, 2013.