File:Umiński - O węglu kamiennym.djvu

This work is in the public domain in the United States because it was first published outside the United States prior to January 1, 1929. Other jurisdictions have other rules. Also note that this work may not be in the public domain in the 9th Circuit if it was published after July 1, 1909, unless the author is known to have died in 1953 or earlier (more than 70 years ago).[1]

This work might not be in the public domain outside the United States and should not be transferred to a Wikisource language subdomain (or as a file it should not be migrated to the Wikimedia Commons) that excludes pre-1929 works copyrighted at home.