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Can anyone tell me where I could post an old photograph of a portrait to find out whether anyone can identify the subject for me? I'm not sure what country the painting originates from but I am thinking that there is a Spanish connection because the back of the photo has the stamp of the photographer's (the only part that I can decipher is Madrid). I'd appreciate any help going.
(p.s. I've taken the liberty of attaching the photo and the stamp on the back).