stackable mid century  

Thonet
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amazing, what year was the...
amazing, what year was the ad from and do you know the name of the style of chair? I've been looking at other pieces of theirs and can't find a match.

No idea
I found that on the internet. Someone has one on ebay saying it was designed by URSULA MEYER but I have not found anything on the internet to back that up. Not sure if it really matters who designed them though. What I have learned in my short career of collecting is that if you see something that may be "something" and the price is right just buy it. Someone else is always there to scoop it up in those few hours (sometimes even minutes)of deliberating. When you lose out you end up mulling it over until something else comes along.
How much are they asking for each chair?

It's an estate sale so I...
It's an estate sale so I won't know what they are asking until I get in the door. They have several other bentwood chairs as well.

she was a freelance designer...
she was a freelance designer for Thonet from 1944-1953

Apperently she has a book...
Apperently she has a book titled "Conceptual art" copyright 1972 "First Edition" - Ursula Meyer, sculptor and writer, Associate Professor of Art at Herber M. Lehman College of the City University of New York. Her work is in the premanent collections of the Finch College Museum, The Brooklyn Museum, The Neward Museum and the Larry Aldrich Museum. Book contains b/w photos and b/w illustrations.