The Society for Seventeenth-Century Music maintains an active website useful for both musicologists and music librarians (https://sscm-sscm.org/). In addition to current information about the organization and its membership, the site offers links to the society’s free online journal (https://sscm-jscm.org/) and an interesting series of bibliographic publications collectively titled JSCM Instrumenta. The series currently consists of five noteworthy publications, resources that might not be well-known among music librarians.
Volume 1 : Chambonnières: A Thematic Catalogue, compiled by Bruce Gustafson
Volume 2 : A Catalogue of Motets, Mass, Office, and Holy Week Music Printed in Italy, 1516–1770, compiled by Jeffrey Kurtzman and Anne Schnoebelen
Volume 3 : Thematic Catalogue of Chamber Cantatas by Marc’Antonio Pasqualini, compiled by Margaret Murata
Volume 4 : A Thematic Locator for the Works of Jean-Baptiste Lully, compiled by Bruce Gustafson with Matthew Leshinskie
Volume 5 : Worship Culture in a Lutheran Court Chapel: Sacred Music, Chorales, and Liturgical Practices at the Dresden Court, ca. 1650–1680, compiled by Mary E. Frandsen
The left sidebar displays the contents of each source with links to separate sections displayed online in a PDF format chapter by chapter. Individual resources are described separately and also presented as links to PDF pages. These resources are mostly recent publications and volumes 1 and 2 were updated in late 2019 and January 2020. All are indexed and accessible through MusRef here