Columbia subject headings:
Christianity--Europe--Congresses.
Evangelistic work--Europe--Congresses.
Secularism--Europe--Congresses.
Harvard subject headings:
Christianity--Europe--History--21st century--Congresses.
Church history--21st century--Congresses.
Evangelistic work--Europe--Congresses.
Secularism--Europe--Congresses.
Princeton subject headings: