Columbia subject headings:
Church history--Primitive and early church, ca. 30-600--Congresses.
Conversion--Christianity--History of doctrines--Early church, ca. 30-600--Congresses.
Evangelistic work--History--Early church, ca. 30-600--Congresses.
Harvard subject headings:
Church history--Primitive and early church, ca. 30-600--Congresses.
Conversion--Christianity--History--To 1500--Congresses.
Princeton subject headings: