It is very unlikely that this work is public domain in the EU, or in any country where the copyright term is life-plus-70 years. However, it is in the public domain in Canada (where IMSLP is hosted) and other countries where the term is life-plus-50 years (such as China, Japan, Korea and many others worldwide). As this work was first published before 1924 or failed to meet notice or renewal requirements to secure statutory copyright with no "restoration" under the GATT amendments, it is very likely to be public domain in the USA as well.
|Genre Categories||;; ; ;|
|Work Title||Violin Sonata|
|Alternative. Title||Sonate en ut# mineur pour violon et piano Horst Platen. (1906)|
|I-Catalogue NumberI-Cat. No.||IHP 1|
|Key||C♯ minor (to E major)|
|Year/Date of CompositionY/D of Comp.||1906|
|Composer Time PeriodComp. Period||Early 20th century|
The 1907 June 1 Musical Times, page 427, mentions this in a list of New Foreign Publications. So first published no later than 1907.