The New Grove Dictionary of Music and Musicians (Volume 12): Meares - Mutis

Now available in a deluxe paperback edition, The New Grove Dictionary of Music and Musicians is the world's greatest music encyclopedia. This unique 20-volume set is packed with over 18,000 pages of information on the history and development of music, instruments, musical forms and terms, musical cities and institutions, and, above all, thousands of eminent composers and performers. The text is fully illustrated with photographs, drawings and musical examples, and all major articles include extensive bibliographies. Entries on composers are accompanied by detailed lists of compositions, which, for example, list the precise instrumentation required for many compositions. These acclaimed worklists alone are a valuable resource for today's musician.
The New Grove Dictionary of Music and Musicians includes:
BL Ancient, Medieval, and Renaissance music--insights on composers as well as new appraisals of theorists, philosophers, and chroniclers. It explores early musical rites, forms, styles and genres, and the social and historical forces that shaped the music of these eras
BL Composers--the first aim of Music and Musicians is to tell you virtually everything you will want to know about the people who have been writing music, from ancient times onwards
BL Ethnomusicology--discover Polynesian chants, Uzbek teahouse ensembles, Xhosa wedding songs, cowboy laments, modern protest songs, and other manifestations of non-western and folk music
BL Forms and genres--harmony, counterpoint, rhythm and melody--the basic materials of music. Symphony, opera, cantata, concerto, motet, oratorio and sonata--these and other genres are surveyed historically and their repertoires outlined
BL Performers--Music and Musicians covers influential figures from the world of popular music, jazz and opera; it explores the lives of patrons and poets, novelists and scientists, dancers and instrument makers, everyone whose work influences music
BL Places and institutions--travel from London to Vienna, Dresden to Osaka, Paris to Pittsburgh. Explore top musical arenas such as Carnegie Hall, Lincoln Center, and Covent Garden

This is the big one -- 20 thick volumes packed full of information on musical history, composers, artists and more. It carries a big price tag, but it's an invaluable aid for the serious student or writer. Grove has several other dictionaries, opera and jazz among them, but if you can only handle one, this is the one to get. This text refers to the 20 Volume edition of this title.