Question: The Emerald Wand of Oz was published by the comapny that is headquartered in what city?
Sentence (from "HarperCollins"): The company name is a combination of several publishing firm names: Harper & Row, an American publishing company acquired in 1987, whose own name was the result of an earlier merger of Harper & Brothers (founded 1817) and Row, Peterson & Company; together with UK publishing company William Collins, Sons (founded 1819), acquired in 1990.
Relevant evidence: No