Answer the following question: Given the following passage  "The Cubs enjoyed one more pennant at the close of World War II, finishing 98–56. Due to the wartime travel restrictions, the first three games of the 1945 World Series were played in Detroit, where the Cubs won two games, including a one-hitter by Claude Passeau, and the final four were played at Wrigley. In Game 4 of the Series, the Curse of the Billy Goat was allegedly laid upon the Cubs when P.K. Wrigley ejected Billy Sianis, who had come to Game 4 with two box seat tickets, one for him and one for his goat. They paraded around for a few innings, but Wrigley demanded the goat leave the park due to its unpleasant odor. Upon his ejection, Mr. Sianis uttered, "The Cubs, they ain't gonna win no more." The Cubs lost Game 4, lost the Series, and have not been back since. It has also been said by many that Sianis put a "curse" on the Cubs, apparently preventing the team from playing in the World Series. After losing the 1945 World Series to the Detroit Tigers, the Cubs finished with winning seasons the next two years, but those teams did not enter post-season play.",  answer the following question. Note that the answer is present within the text.  Question: Who incurred the Curse of the Billy Goat?
Answer:
P.K. Wrigley