The Liber Usualis. The first page says, The Liber Usualis No 801, this page has several bend marks. There is some shelf wear, the first page and the last page have age related discoloration. It is 5" across, by 7 1/2" high by 2 1/4" wide. Slightly over 2 1/2lbs. Interior pages have a slight wave. Printed in Belgium, 1956.