Book of prayers, chants, and lessons used by Roman Catholic monks first published in 1896. a modern-day chant book which contains chants, prayers and readings for major services (particularly the mass) throughout the church year. The Liber is not a critical edition, for it conflates practices of different times and places, but it is a standard reference for "typical" plainchant services. Items for a particular service are scattered (the propers in one place, the ordinary chants and texts in another). Consult the table of contents to find items from the ordinary. An index, divided by genres, is located approximately 9/10 of the way through the book.