Columbia subject headings:
Harvard subject headings:
Catholic Church--Liturgy--Texts--History and criticism.
Divine office--Liturgy--Texts--History and criticism.
Funeral service--Catholic Church--Liturgy--Texts--History and criticism.
Liturgics--Data processing.
Princeton subject headings:
Catholic Church--Liturgy--Texts--History and criticism.
Catholic Church. Officium pro defunctis
Divine office--Liturgy--Texts--History and criticism.
Prayers for the dead--History.