Schaff, Philip. "Philotheos Bryennios." The Oldest Church Manual Called the Teaching of the Twelve Apostles. Second Edition, Revised and Enlarged. New York: Funk & Wagnalls, 1886, 8-9.
Schaff observes that the manuscript of the Didache, the "Jerusalem" manuscript, was not known, though it was in the library in a volume cataloged in 1845, 1856, and 1858. The actual Didache text was discovered by Philotheos Bryennios, Metropolitan of Nicomedia, in 1873 (Schaff 1886, 8). In Schaff's estimation, Bryennios was a thoroughgoing scholar, familiar with patristic literature and current German scholarly literature.