Susanne van Soldt Manuscript
The Susanne van Soldt Manuscript is a keyboard anthology dated 1599 consisting of 33 pieces copied by or for a young Flemish or Dutch girl living in London. Its importance lies mostly in the fact that it is the only known source of early Dutch keyboard music prior to Sweelinck.
Source: Wikipedia — Susanne van Soldt Manuscript (CC BY-SA 4.0)