Question: What was the book about people in the dust bowl called that the author who published The wayward bus wrote?
Answer(s):
answer: The Grapes of Wrath

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SELECT DISTINCT ?x
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FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
?c ns:book.author.book_editions_published ns:m.04vh4n0 . 
?c ns:book.author.works_written ?x .
?x ns:common.topic.notable_types ns:m.01xryvm .
?x ns:book.written_work.subjects ns:m.0g89m .
}