Toosbuy turned that simple idea into global shoe brand Ecco.

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It was the Shoe drawing, which was turned down in 1956.

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"It takes a lot of shoe leather, " says Mr. Salguero, 30, who turned to entrepreneurship after getting laid off from a real-estate development firm.

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Enlisting archaeologist Tom King, a shoe was recovered in a location with circumstantial evidence of Earhart's plane, but nothing substantial has turned up.

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