Unknown Danish armchair  

Danish furniture makers mark on the bottom

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@molassekoeniggmx-de.  I have tried to identify these chairs or similar ones before.

Kai Lyngfeldt Larsen is attributed as designer . 

You will find examples that have Soren Willadsen labels but these have stretchers between the front and back legs but, other than that difference, they match your chairs. Maybe the stretchers were added for stability?

And Soren Willadsen  apparently did not do much advertising; 

Link to previous discussion; @leif-ericsen posted some useful information.

https://designaddict.com/community/identification/need-help-with-a-soren-willadsen-table/#post-179756