U.S. Presidents: Madison, Nixon, and Clinton: Crack the easy-level codes and explore their lives

Exodus- The Kashmir Files

U.S. Presidents: Kennedy and Bush: Crack the medium-level codes and explore their lives

AP® European History Crash Course Book + Online

U.S. Presidents: Adams and Wilson: Crack the difficult-level codes and explore their lives

Thirty-Six Years in the White House: By the Doorkeeper (Annotated)

U.S. Presidents: Washington, Lincoln, and Grant: Crack the medium-level codes and explore their lives