Columbia subject headings:
Manuscripts, Medieval--Social aspects--Congresses.
Outer space--Social aspects--Congresses.
Written communication--Social aspects--Congresses.
Harvard subject headings:
Manuscripts, Medieval--History--Congresses.
Space perception--Congresses
Space--Congresses.
Princeton subject headings:
Manuscripts, Medieval--Social aspects--Congresses.
Space--Social aspects--Congresses.
Written communication--Social aspects--Congresses.