 Complete the following phrase:  During World War II the regiment mobilized 13 railway engineer battalions and three railroad operation battalions. The battalions saw service in Libya and Tunisia during the Western Desert Campaign and Tunisian Campaign, in Southern Ukraine as part of the Italian Expeditionary Corps in Russia, in Yugoslavia, Albania, Greece and France. In 1941 the 9th Company of the IV Railway Engineer Battalion built a combined road and rail bridge over the Corinth Canal, using an Austrian . The same battalion repaired the bridge over the Gorgopotamos river after the British-Greek 