Columbia subject headings:
Harvard subject headings:
Indo-European languages--Morphophonemics--Congresses.
Indo-European languages--Phonemics--Congresses.
Indo-European languages--Phonetics--Congresses.
Princeton subject headings:
Indo-European languages--Morphophonemics--Congresses.
Indo-European languages--Phonemics--Congresses.
Indo-European languages--Phonetics--Congresses.