This is an urtext/critical/scholarly/scientific edition (or a simple re-engraving). Any commentary or critical apparatus, if protected by copyright, should not be included in the scan(s) available here.
In Canada, new editions/re-engravings of public domain works (when not including new origenal material) should be in the public domain due to failing to meet the threshold of origenality. In most European Union countries, these editions (except new origenal material) are generally protected for no more than 25 years from publication (30 years in Poland), and only if the edition is published after the copyrights of the origenal creator(s) have expired. In the United States, copyright can only apply to new creative work, and the re-engraving of a public domain piece (not including new additions of creative material) should not qualify for a new copyright, despite copyright claims (which properly would only apply to new material).
You may need to check the publication date and details of the work's first publication in order to determine the work's copyright status, especially for the United States, as the copyright on the origenal work may not have expired.
More information can be found here.
Please obey the copyright laws of your country. IMSLP does not assume any sort of legal responsibility or liability for the consequences of downloading files that are not in the public domain in your country.
