Viana, M., and G. Nappi. “Cyclic Migraine. From Pathophysiological Understanding to Therapeutic Opportunities in Patients With Migraine Attacks Showing Predictable Periodicity”. Confinia Cephalalgica Et Neurologica, vol. 26, no. 1, July 2016, pp. 26-29, https://www.mattioli1885journals.com/index.php/confinia/article/view/5534.