Columbia subject headings:
Language and languages--Variation--Congresses.
Languages in contact--Congresses.
Linguistics--Congresses.
Harvard subject headings:
Language and languages--Congresses
Language and languages--Europe--Congresses.
Linguistic change--Congresses.
Princeton subject headings:
Language and languages--Variation--Congresses.
Languages in contact--Congresses.
Linguistics--Congresses.