APA-referens (7:e uppl.)

Keller, D. J. (1959). Fundamentals of Gregorian chant: A basis for class notes and study (5th rev. ed.). Liturgical Press.

Chicago-referens (17:e uppl.)

Keller, Dominic J. Fundamentals of Gregorian Chant: A Basis for Class Notes and Study. 5th rev. ed. Collegeville, Minn.: Liturgical Press, 1959.

MLA-referens (8:e uppl.)

Keller, Dominic J. Fundamentals of Gregorian Chant: A Basis for Class Notes and Study. 5th rev. ed. Liturgical Press, 1959.