 Complete the following phrase:  One of the most important early operations of the Greek resistance movement in which Velouchiotis and his fighters, after negotiations with the British, agreed to participate alongside Napoleon Zervass republican EDES resistance forces and twelve British saboteurs under the leadership of Major E. C. W. Eddie Myers was the blowing-up of the Gorgopotamos railway viaduct, south of Lamia, on November 25, 1942 