Cnp balkans aircraft 02.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 balkans aircraft 02, Lewis Gun
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en
Cnp balkans aircraft 02, British anti-aircraft gunners in the Balkans., British anti-aircraft gunners in the Balkans.
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バルカンス製航空機
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Cnp balkans航空機 02、バルカン半島のイギリスの対空砲手。バルカン半島のイギリスの対空砲手。
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balkans balkan country balkan peninsula balkan wars asserted