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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The privately held retailer is owned by husband and wife, Do Won (Don) Chang and his wife Jin Sook Chang, who moved to the U.S. from South Korea in 1981 and eventually became U.S. citizens.

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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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