(1920). International Congress of Gregorian Chant: Held at the Metropolitan Cathedral Church of St. Patrick, New York, on June 1st, 2nd and 3rd, 1920. [publisher not identified].
Chicago-referens (17:e uppl.)International Congress of Gregorian Chant: Held at the Metropolitan Cathedral Church of St. Patrick, New York, on June 1st, 2nd and 3rd, 1920. New York: [publisher not identified], 1920.
MLA-referens (8:e uppl.)International Congress of Gregorian Chant: Held at the Metropolitan Cathedral Church of St. Patrick, New York, on June 1st, 2nd and 3rd, 1920. [publisher not identified], 1920.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.