RILM Music Encyclopedias is available for use through May 31, 2020 due to the COVID-19 crisis.
Description from the publisher:
RILM Music Encyclopedias is a continually expanding curated full-text collection that currently comprises 57 titles published from 1775 to the present. Its content spans various fields and subject areas of historical musicology, ethnomusicology and theory, with focus on topics ranging from popular music, opera, instruments, blues and gospel, to recorded music and women composers.