Honda and Nissan had already decided to go it alone when GM and Toyota created NUMMI.

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Thus when Toyota took over the strike-ridden NUMMI plant in California from General Motors in the 1980s, the previous intractable labor disputes vanished.

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The coins, mainly bronze Nummi, were found in layers within the clay jar, with those at the top dating from between 333-335 AD, and the coins at the bottom at least 10 years older.

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Since joining Toyota in 1984, Toyoda has worked in NUMMI, headed the China operations and introduced Internet services at Toyota, when such projects were still relatively rare, because of his personal interest in online technology.

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Toyoda said Hogan was someone he trusted, having known him since they worked together more than a decade ago at NUMMI, or New United Motor Manufacturing, a California auto plant jointly run by Toyota and GM.

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Hogan, an independent consultant and former GM group vice president, has been Toyoda's friend since they worked together more than a decade ago at NUMMI, or New United Motor Manufacturing, a California auto plant jointly run by Toyota and GM.

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