Hans Olsen for Bramin. Check out this thread about them:
https://www.designaddict.com/forum/Identification/Danish-lounge-chair-ID
Leif Ericsen posted a photo of the brochure with the designer and maker (scroll down).
Your chair looks very close to a Hans Olsen design for Bramin. The shell looks slightly different in yours. That could be due to camera angle, extreme wear on the piece, or perhaps a slight change of form during the years of production.
The alternative would be that someone wanted to make a chair that looked a lot like Olsen's design. Here is a link with a Bramin sticker, as well as a 1960 Furniture Forum spread with Olsen's design.
https://www.1stdibs.com/furniture/seating/lounge-chairs/hans-olsen-loung...
Good to know. This one looks like it would be a later production with the exposed black hex-head bolts on the sides.
Also, after taking a closer look at the original photo again, I guess that dip in the front part of the shell seat could be just loose fabric that is hanging down. I initially read that as the shell itself was formed to hang over the front stretcher.
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