sentences:  It is said to have originally consisted of 27 stanzas, with each following stanza beginning with the consecutive letter of the alphabet.Surviving manuscripts may be found in a c. 1361 Dublin Troper (a music book for use at Mass) and a 13th or 14th century vellum Sequentiale that may have been connected with the Church of Addle, Yorkshire.Its lyrics also appear in the works of John Audelay (perhaps a priest, he definitely spent the last years of his life at Haughmond Abbey, where he wrote for the monks), in a group of four Marian poems.