The death occurred in April 1998 of the Argentinean mathematician Alberto P. Calderón, whose influence was very important not only in his native country, but also in the Ibero-American world and internationally. On this occasion we offer two papers related to Calderón which were originally published in Spanish. The first is an obituary note on Calderón written for the Spanish newspaper El Pais by former ICMI President Miguel de Guzmán. The second paper, which will allow the reader to grasp the flavor of Calderón's style, is the complete text of a lecture given by Calderón himself at a joint meeting of Argentinean mathematicians and mathematics educators ten years prior to his death and in which he presents his views on the "learning and teaching of mathematics" (the reader will note the order in which Calderón puts these words). The original Spanish versions of these texts can be accessed on the websites
I would like to thank my colleague ICMI Vice-President Néstor Aguilera for translating these texts from Spanish. I also want to express my gratitude to Luis Puig and Carolyn Kieran for their help with the final version of the texts.
Bernard R. Hodgson, Secretary