Khalek, N. “The Emergence of Early Sufi Piety and Sunnī Scholasticism: ʿAbdallāh B. Al-Mubārak and the Formation of Sunnī Identity in the Second Islamic Century. By Feryal Salem”. JAOS, vol. 140, no. 1, Sept. 2021, p. 268, doi:10.7817/jaos.140.1.2020.brev001.