Saw you on Mid Century Reddit, thought someone might be able to help here. It's definitely unlike any of the famous cow-horn designs I know.
As I said there however, any more pictures would probably be helpful. Still can't see the construction of the chair, which doesn't help at all.
The seat rails and low thin side stretchers resemble a few Arne Hovmand Olsen designs (by unknown manufacturers). However, I can't recall any AHO designs of the top of my head that are similar to those cow horns.
By the way, in my own vocabulary, I would say that a "cow horn" arm rest would be a design subset of a more generic "elbow chair". So I guess this chair falls under both categories.
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