Frere, W. H., Collamore, L., & Metzinger, J. P. (1990). Frere's index to the antiphons of the Sarum antiphoner: An expanded version. Plainsong and Mediaeval Music Society.
Chicago Style (17th ed.) CitationFrere, W. H., Lila Collamore, and Joseph P. Metzinger. Frere's Index to the Antiphons of the Sarum Antiphoner: An Expanded Version. London: Plainsong and Mediaeval Music Society, 1990.
MLA (9th ed.) CitationFrere, W. H., et al. Frere's Index to the Antiphons of the Sarum Antiphoner: An Expanded Version. Plainsong and Mediaeval Music Society, 1990.
Warning: These citations may not always be 100% accurate.