Free public domain sheet music from IMSLP / Petrucci Music Library
Helsinki: K.F. Wasenius, n.d.(by 1908). Plate K.F.W. 71.
Public Domain - Non-PD EU [tag/del]
This file is part of the Sibley Mirroring Project.
No later than 1908 since Wasenius the publishing house stopped publishing then and changed to the publisher BIS soon after (iirc).
The plate is printed as 'W.F.W. 71' on one page, but this appears to be a typo.
||Impromptu and Scherzo
||D♭ major, C♯ minor