The Brigittine Breviary of Syon Abbey - from the MS with English Rubrics F.4.11 at Magdalene College, Cambridge
Daily Office of the only English religious community to have survived the Reformation
The manuscript edited here in part contains in its entirety also a Psalter, the twelve usual canticles and a litany (all omitted here), and was written after 1422. John Wickham Legg had copied Magdalene in or before 1894 and later H.A. Wilson made another transcript, but it was never published. The Collins edition has reference also to the printed liturgical editions of 1697 and 1908.