Rubén Santantonín (1919–1969) coined the term “cosas” [things] for his artistic production. He used the term “cosas” to refer to his reliefs in cardboard, which were meant to be exhibited on a wall support, as well as for his hanging objects, which were created using lesser or rudimentary materials such as plaster, fabric, cardboard, and wire. In 1965 Rubén Santantonín burned almost all his work, and it is for this reason that the existing photographic records in catalogs or brochures take on special significance.The artists whose works were selected for the Argentine representation at the VII Biennial of São Paulo (1963), in addition to Rubén Santantonín were: Luis Seoane, Aldo Paparella, Juan Carlos Castagnino, Roberto Aisemberg, Kenneth Kimble, Martha Peluffo, and Raúl Russo.Romulado Brughetti, who began his career in the 1940s, is one of the most significant critics in Argentine art. In 1963, he served as the general director of cultural relations in the Ministry of Foreign Affairs.This document is significant because it sheds light on the role Rubén Santantonín played within the national art scene during the first years of the 1960s when he was chosen to represent Argentinean art at the prestigious 1963 São Paulo Biennial (Brazil). This text should be read in conjunction with the other ICAA Documents Project records relating to Santantonín, which reconstruct his role in the Argentine arts milieu.