Aggarwal, Dipika, et al. “A Randomized, Double-Blinded, Placebo-Controlled, Cross Over Study Evaluating the Efficacy and Safety of Timolol Ophthalmic Solution As an Acute Treatment of Migraine”. Kansas Journal of Medicine, vol. 13, no. S2, Feb. 2020, pp. 2-5, https://doi.org/10.17161/kjm.v13i.13495.