Thank you for the post, Smokeeaterpilot. I was wondering the meaning of the "A". Still, the lack of an AEF number on the 1537 photo indicates, to any reasonable person, that it preceded the other two. Also, we now know that all the catalogue photos were not taken in France as previously stated. Many, if not most, of the photos have accompanying data that states where the photo was taken, when it was taken, and who is in the photo. In the case of 1537, there is no such accompanying data, and any speculation as to when and where it was taken is just that, pure speculation. Caution should always be exercised when drawing conclusions from any document. Such is the nature of true research.