Early Knoll Chair  

I just picked up this wonderful early Knoll chair. Does anyone have an idea as to who the designer is? I found a near identical side chair version in one of my books with the same fabric, but all it said was that it was early Knoll. The paper upholstery label states the maker as H.G. Knoll Industries INC., Pennsburg Pennsylvania. Plus the Knoll Associates decal. Its only real flaw is that three of the upholstery buttons are gone. Any help would be great!
Thanks in advance.