Tradition
Eusebius of Caesarea
Church History
Book 4 › Chapter 15 · Part 3 of 3
Under Verus, Polycarp with Others suffered Martyrdom at Smyrna
48. And there are also records extant of others that suffered martyrdom in Pergamus, a city of Asia—of Carpus and Papylus, and a woman named Agathonice, who, after many and illustrious testimonies, gloriously ended their lives.
Source: Church History (New Advent)