question: Princess Ozma lives in the fictional City of Thi in which L. Frank Baum book?
answer: "The Lost Princess of Oz"
context: Title: City of Thi
  Passage: The City of Thi is a fictional city in the Winkie Country of the Land of Oz, from the Oz Books by L. Frank Baum.  Thi appears in the book "The Lost Princess of Oz".
  Title: The Lost Princess of Oz
  Passage: The Lost Princess of Oz is the eleventh canonical Oz book written by L. Frank Baum.  Published on June 5, 1917, it begins with the disappearance of Princess Ozma, the ruler of Oz and covers Dorothy and the Wizard's efforts to find her.  The introduction to the book states that its inspiration was a letter a little girl had written to Baum: "I suppose if Ozma ever got hurt or losted, everybody would be sorry."
  Title: Pastoria
  Passage: King Pastoria is a fictional character mentioned in the Oz books by American author L. Frank Baum.  He was the rightful ruler and King of the undiscovered Land of Oz, but was mysteriously removed from his position when the Wizard of Oz unexpectedly came to the country and took the throne, proclaiming himself as the new dominant ruler of Oz.  Shortly after, Pastoria's infant daughter and only child heir, Princess Ozma suddenly vanished, leaving not a single clue of her whereabouts.
citations: The Lost Princess of Oz City of Thi