Robert D. Heaton, "The Shepherd of Hermas As Scriptura Non Grata: From Popularity in Early Christianity to Exclusion from the New Testament Canon" (Rowman & Littlefield, 2023)
New Books in Biblical Studiesrobert-d-heaton-the-shepherd-of-hermas-as-scriptura-non-grata-from-popularity-in-early-christianity-to-exclusion-from-the-new-testament-canon-rowman-littlefield-2023