thanks for your scans of Pierné and Stenhammer. In general, we prefer it if the uploader can fill in some of the information about the source: for example, for the Pierné, it’s an arrangement for solo piano of the orchestral work (presumably under the aegis of Alphonse Leduc, Editeur as listed at the foot of the page). If you look at the plate number A.L. 7610 and compare it with numbers on the page I linked to above, you’ll see 7610 has to be 1888 or earlier.
The Stenhammer has no such marks to identify the publisher or plate number, and the name of the arranger (Alvin Berger) is fairly unknown. I’m relatively certain the edition is in the public domain, however I cannot be completely certain. Would you please return to the Stenhammer page and fill in the information about the source of your scan, to your best knowledge?