It has a great resemblance with the swivel chair in this thread:
http://www.designaddict.com/forum/General-discussion/Pmj-viby-poul-m-jes...
Well spank me with a wet straw. That is another version of the chair based on the front panel and seat constriction but with different legs and less back rest.
Why do you think it is nanna ditzel? Her work is documented by her design studio and webpage
http://www.nanna-ditzel-design.dk/
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