They include artist Andy Warhol, writer Sylvia Plath and actor/director Robert Redford .

VOA: special.2011.05.27

Finally, it was Robert Plath, who was an airline pilot, who invented a new, wheeled suitcase, which he patented in 1991.

后来一个叫罗伯特·普拉斯的飞行员，发明了一种滚轮行李箱，并且在1991年取得专利权。

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