Among his collaborators were Ciro Alegría, Carlos Cueto Fernandini [es], Manuel Mujica Gallo and Mario Vargas Llosa.

[6] On January 2, 1970, Manuel Ulloa resigned as president of the board of directors of Editora Nacional S. A. because a Government decree prevented those who resided outside the country for more than six months from exercising such function.

[6] On March 4, 1970, Expreso and Extra were practically expropriated by the military government, with the excuse of handing over their administration to their own employees and workers, organized in cooperatives.

"[6] After the revolutionary government ended on July 28, 1980, Expreso and Extra returned to their owners, and Manuel Ulloa took over again as president of the board of Editora Nacional S. A.

It then had a prestigious team of journalists, among which Jaime de Althaus [es], Jorge Morelli, Uri Ben Schmuel and Patricio Ricketts stood out.