Not only can we now identify it, but if you click the corresponding note, Jeff Haythorpe has sent me a scan and tells me he bought it at the exhibition. What better authority could a researcher want?
It appears to be an unpublished part of the series for the Look and Learn magazine/comic called The Story of World War One (LOOK AND LEARN 437 - 462 - 30/05/70 - 21/11/70)
Many thanks to Jeff...again!
