Columbia subject headings:
Harvard subject headings:
Comparative linguistics--Congresses.
Language and languages--Variation--Congresses
Languages in contact--Congresses.
Languages, Mixed--Congresses.
Princeton subject headings:
Celtic languages--Social aspects--Congresses.
Dialectology--Congresses.
Languages in contact--Congresses.
Linguistic geography--Congresses.
Romance languages--Social aspects--Congresses.
Sociolinguistics--Congresses.