RILM Music Encyclopedias: A full-text collection of 57 titles published from 1775 to the present with content spanning “historical musicology, ethnomusicology and theory, with focus on topics ranging from popular music, opera, instruments, blues and gospel, to recorded music and women composers.”
RIPM Jazz Periodicals: A collection of “105 rare, full-text periodicals published from 1914 to 2006” focusing primarily on American jazz. Significant journals include Cadence, Mississippi Rag, and Record Changer.
RIPM European & North American Music Periodicals (Full Text): Accessible via the RIPM website, this preservation search system offers “100 rare, full-text journals comprising some 540,000 pages." See more information here.