 Complete the following phrase:  It played significant roles in the operations at Fort Eben-Emael, the Battle of Crete, and in the rescue of Benito Mussolini. It was also used in North Africa. However, it was used chiefly in supplying encircled forces on the Eastern Front such as supplying the Demyansk Pocket, the Kholm Pocket, Stalingrad, and the defenders of 