Cnp aust artillery 01.jpg
Originally scanned from: GWS - The Great War: The Standard History of the All Europe Conflict (volume four) edited by H. W. Wilson and J. A. Hammerton (Amalgamated Press, London 1915)

According to http://www.firstworldwar.com/photos/sources.htm, “Each photo is believed to be copyright-expired except where indicated.” The site has been up for seven years and sources for the photos cited so it is reasonable this claim of copyright expired status has stood the test of time.

Note: other than the source of the image and the assertion of copyright free status, detail information such as credits for each photographer and image provider was not indicated for each image.
en
Cnp aust artillery 01, Australian heavy artillery., Australian heavy artillery.
commons
en
Cnp aust artillery 01, BL 6 inch Mk XIX gun
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ja
Cnp aust砲兵01、オーストラリアの重砲。
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ja
クンプ・オースト砲 01、BL 6インチ Mk XIX
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artillery asserted