Complex sentence: In a convincing case, Kravchenko's lawyers presented witnesses who had survived the Soviet GULAG, including Margarete Buber-Neumann, the widow of German Communist Heinz Neumann, who had been shot during the Great Purge.
Split into simpler sentences: In a convincing case, Kravchenko's lawyers presented witnesses who had survived the Soviet GULAG. Among them was Margarete Buber-Neumann, the widow of German Communist Heinz Neumann, who had been shot during the Great Purge.