File:Diagram Of Crater Mine Galleries And Saps.png
This tag can be used only when the author cannot be ascertained by reasonable enquiry. If you wish to rely on it, please specify in the image description the research you have carried out to find who the author was. The above is all subject to any overriding publication right which may exist. In practice, publication right will often override the first of the bullet points listed.
Unpublished anonymous paintings remain in copyright until at least 1 January 2040. This tag does not apply to engravings or musical works. More information