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Charles F. Kettering and colleagues , working at the various incarnations of Electro-Motive and at the General Motors Research Corporation during the 1930s , advanced the art and science of two-stroke diesel technology to yield engines with much higher power-to-weight ratio s than the two-stroke diesels of old .
 Charles F. Kettering, Electro-Motive
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Answer:
 Charles F. Kettering, Electro-Motive