Columbia subject headings:
Architecture, Early Christian--Congresses.
Baptism--History--Early church, ca. 30-600.
Baptisteries--Congresses.
Harvard subject headings:
Architecture, Early Christian--Congresses.
Baptism--History--Early church, ca. 30-600--Congresses.
Baptisteries--History--Congresses.
Christian antiquities--Congresses.
Princeton subject headings:
Architecture, Early Christian--Congresses.
Baptism--History--Early church, ca. 30-600.
Baptisteries--Congresses.