Columbia subject headings:
Gregorian chants--History and criticism.
Montpellier codex.
Musical intervals and scales.
Harvard subject headings:
Gregorian chants--History and criticism.
Musical intervals and scales.
Université de Montpellier. Faculté de médecine. Bibliothèque. Manuscript. H. 159.
Princeton subject headings:
Gregorian chants--History and criticism.
Montpellier codex.
Musical intervals and scales.