7. Vale, Arnaldo. "Sobre a concepção de partido." N.p.:, March 1981.

7. Vale, Arnaldo. "Sobre a concepção de partido." N.p.:, March 1981., 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/374422 Accessed September 26, 2026.