I think the NSU/Audi Ro-80 [0, 1] predates Mazda, isn't? And Mazda (as well as Citroen and others) used this engine, I think. [0] https://en.wikipedia.org/wik

I think the NSU/Audi Ro-80 [0, 1] predates Mazda, isn't? And Mazda (as well as Citroen and others) used this engine, I think. [0] https://en.wikipedia.org/wiki/NSU_Ro_80 https://en.wikipedia.org/wiki/NSU_Ro_80 [1] https://en.wikipedia.org/wiki/Wankel_engine#Early_developments https://en.wikipedia.org/wiki/Wankel_engine#Early_developmen...