2. Freitas, André. "Construir o PT.Construir o partido revolucionário." N.p.:, 1981 July 18.

2. Freitas, André. "Construir o PT.Construir o partido revolucionário." N.p.:, 1981 July 18., Box: 19. Eduardo Sarno Collection of Leftist Movements in Brazil, 2002-03. Benson Latin American Collection, The University of Texas at Austin. https://archives.lib.utexas.edu/repositories/4/archival_objects/374469 Accessed September 26, 2026.