List of women music publishers before 1900
Women music publishers have existed since the late 16th century, but were comparatively rare before the 20th century. Most of these names were extracted from searching WorldCat using prefixes such as "Veuve" or "Witwe" and their variants (both meaning widow in French and German respectively).
Source: Wikipedia — List of women music publishers before 1900 (CC BY-SA 4.0)