Columbia subject headings:
Harvard subject headings:
Grammar, Comparative and general--Morphology.
Grammar, Comparative and general--Phonology
Grammar, Comparative and general--Syntax.
Language and languages--Variation
Linguistic change--Variation.
Princeton subject headings:
Grammar, Comparative and general--Morphology.
Grammar, Comparative and general--Phonology.
Grammar, Comparative and general--Syntax.
Language and languages--Variation.
Linguistic change--Variation.