Ircam - Georges Pompidou Center - Institute of Research and Coordination in Acoustics - Music.
Digital Image Archive of Medieval Music - Archive of Early and Medieval music manuscripts and scores. Hundreds of scanned images available, with higher resolution ones for members.
German National Discography - Listing of all 78RPM recordings made in Germany from 1890-1960.
Brazilian Music Archives - Selection of manuscripts from the Mariana Museum of Music, including rare compositions of religious music from the 17th to 20th centuries, composed mainly by lesser known Brazilian artists. Read about the pieces and view facsimiles of each page.
The Keys of Atlantis - Chapter 1 of this book by Peter Wakefield Sault, that is concerned with the mathematical derivations of the western system of music, the Babylonian unit of rotation and the minute of time.
American Music Resource - Searchable database of primary bibliographical and Internet sources for American music.
Columbia University Directory of Musicology Dissertations - Listing and abstracts for every successfully defended Columbia University musicology, music theory, ethnomusicology, and music history dissertation from 1986 to the present.
Archive of Dissertation Abstracts in Music - Includes about 120 abstracts providing links to full dissertations. New submissions are welcome.
Web Resources for Research in Music - A collection of links provided by Music Department of the University College Cork.
A Chronology of the Symphony 1730-1998 - Lists hundreds of symphonies grouped by composer, then year by year.
WWW Sites for Musicologists - Extensive collection of links.