Moving outside the topic of Latin American stamps for a while, here’s a bit of a mystery that’s been puzzling me some time: a Bulgarian cinderella stamp. What makes this very interesting is the inscription, ‘допълнителни пощенски услуги’ which (Google) translates as ‘additional postage (stamp)’. My initial thought was that this might be some kind of obligatory postal tax stamp. But this item is nowhere to be found on general stamp catalogues!?
Based on the looks and design, this was likely put out sometime between 1920s to 1940s. As this is imperforate, I would not exclude the possibility of this being a cut out from postal stationary neither.
As usual, any help in identifying this accurately would be greatly appreciated.
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