Christian Teachers in the Centuries After the Apostles
- Introduction to the Study of Church Fathers: H. B. Swete – Patristic Study (1902)
- Edgar J. Goodspeed – Index Patristicus (1907) – Index of Greek words that occur in the church fathers.
- NT quoted and commented on by Church Fathers: e-catena (chapter-by-chapter, verse-by-verse index – 12,517 cross-references)