This Friday I spent my time tackling one of the hardest cataloging medias, music CDs. They are difficult because they are all produced and processed differently. Most products have an International Standard Book Number (ISBN). Some media also gets assigned a number and some do not. What music media gets is a music number. This number is also sometimes difficult to locate. Most of the time it is printed on the spine of the CD. When it is not there you have to go hunting for it. Thankfully this number is searchable on OCLC. So while at the Glen Ellyn Public Library I searched OCLC for about 30 music CD bibliographic records using the music number. The cover to the left is not one I searched for but as you can see it has a music number.