While Chang watches the books, his wife, Jin Sook, keeps an eye on fashion as head buyer.

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Jin Sook Chang, who immigrated from Korea and with her husband Do Won launched clothing retailer Forever 21, now with nearly 500 stores.

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Other notable American newcomers include Do Won and Jin Sook Chang, the cofounders of Forever21, and Chris Cline, who owns 3 billion tons of coal reserves, mostly in Illinois.

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