Corresponding sides are a pair of matching sides in two different shapes (size does not matter). In the field of geometry, the concept of corresponding sides plays an important role to prove various triangular theorems.
The Boeing B-17 Flying Fortress is a four-engine heavy bomber aircraft developed in the 1930s for the United States Army Air Corps (USAAC).
 Flying Fortress  is the twenty-fifth episode of the Sonic Underground television series and the first of three episodes in the Chaos Emerald Crisis mini-series. It first aired on 31 March 1999 in France and on 1 October 1999 in the United States.