In the book The Egypt Game, who owns the A-Z store on Orchard Street?

When April moves to the Casa Rosada to live with her grandmother, she takes an interest in a dusty curio shop with a sign that says A - Z. The store is owned by a mysterious, taciturn man whom residents of the area call the Professor. People in the community are skeptical and suspicious of the Professor, partly because he is a man of few words who doesn't easily form relationships, and partly because his appearance is forbidding. His scraggly beard and dark, empty eyes make him appear strange. Unfortunately, when two unsolved murders of children occur in the neighborhood about a year apart, people in the community suspect the Professor without any real grounds. The man who owns the variety store, Mr. Schmitt, actually circulated a petition and encouraged people to write letters to get the Professor to leave the neighborhood. At the end of the book, the Professor helps save April from the real murderer, a cousin of Mr. Schmitt. April learns that the Professor's real name is Dr. Huddleston. On Christmas Eve, he visits the children at April's apartment and tells them his story and how he came to own the A - Z store. As a result of the Egypt game and the attack on April, Dr. Huddleston takes a renewed interest in his store and in life.