 Complete the following phrase:  After Operation Barbarossa, German troops had encircled Leningrad, and began the siege of Leningrad. Several operations had been designed by the Soviet commanders in the area to liberate the outskirts of Leningrad from the Germans. In the fall of 1943, preparations had begun to design another plan to retake the outskirts of Leningrad from the Germans, after the only partially successful 