The Apostolic Fathers

"'Apostolic Fathers' is the name given to a certain number of writers or writings (several of which are anonymous) dating from the end of the first or from the first half of the second century. The name has been selected because the authors are supposed to have known the Apostles and also because their works represent a teaching derived immediately, or almost immediately, from the Apostles. These writings are, indeed, a continuation of the Gospels and of Apostolic literature (http://www.earlychristianwritings.com/tixeront/section1-1.html#polycarp.)"

 A Handbook of Patrology by J. Tixeront

Reference:

http://www.earlychristianwritings.com/tixeront/section1-1.html#polycarp