The New Grove Dictionary of Music and Musicians, 2nd edition (NNGII)
Published in January 2001, the  New Grove II is the first new edition of this landmark music reference work in over 20 years. Publication also marks the first time in Grove history that The New Grove has been available in both print and electronic formats, making it more accessible than ever before. One caveat - check both formats.  The electronic version is updated regularly, but it is often easier to get a sense of the whole in the print version. Located in Ready Reference and at the Index Table, and from
http://www.library.uiuc.edu/mux (our homepage). Older editions are still available in the Reference Stacks. Sometimes they give information deleted from later versions. The online database includes the full text of The New Grove Dictionary of Music and Musicians, second edition, the New Grove Dictionary of Jazz, second edition, and The New Grove Dictionary of Opera.