The 39 Clues: The Cahill Files #1: Operation Trinity
(The 39 Clues #18)
by Clifford Riley

• Publication Date: May 8, 2012
• Genres: Adventure, Fiction, Mystery
• Hardcover: 144 pages
• Publisher: Scholastic Inc.
• ISBN-10: 0545431433
• ISBN-13: 9780545431439