Comparison of maximum pain intensity and duration of primary dysmenorrhea after acupressure on third liver and placebo points - A double-blind randomized controlled clinical trial - Kafaei Atrian, Mahboobeh; Afshar, Mohammad; Sarvieh, Malihe; Mirbagher Ajorpaz, Neda; Karimian Taheri, Zahra; Asghari Jafarabadi, Mohammad; Heshmat, Reza (Nursing Practice Today, 2015)