Columbia subject headings:
German language--Dialects--Rhine River Valley.
German language--Social aspects--Rhine River Valley.
Sociolinguistics.
Harvard subject headings:
German language--Dialects--Rhine River Valley.
German language--Social aspects--Rhine River Valley.
Sociolinguistics.
Princeton subject headings:
German language--Social aspects--Germany (West)--North Rhine-Westphalia.
Speech and social status--Germany (West)--North Rhine-Westphalia.