- Letters attributed to [Clement of Rome]
- The [First Epistle of Clement]
- The [Second Epistle of Clement](https://en.wikipedia.org/wiki/Second_Epistle_of_Clement "Second Epistle of Clement")_ (contested authorship; see [§ Clement of Rome]
- Seven epistles of [Ignatius of Antioch]
- The [Martyrium Ignatii]
- The [Epistle of Polycarp]
- The [Martyrdom of Polycarp]
- Fragments of the writings of [Papias of Hierapolis], which have survived as quotations in later writers
- One short fragment of the Apology of [Quadratus of Athens]
- The [Didache]
- The [Epistle of Barnabas]
- The [Epistle to Diognetus]
- The [Shepherd of Hermas]