 Complete the following phrase:  In the 1960s Rogelio Ortega was one of the leading Cuban chess players. He twice won Cuban Chess Championship in 1958 and 1966. Also Rogelio Ortega was silver medalist of the Cuban Chess Championship in 1969. He was participant in several major international chess tournaments: several Capablanca Memorial, Chigorin Memorial, Lasker Memorial, two Rubinstein Memorial, U.S. Open Chess Championship and others. In 1967, Rogelio Ortega represented Cuba in the Zonal Chess tournament of the 