  In Colombia, as in other countries in the region, the first works in analytic philosophy were produced in the second half of the twentieth century. There are two journals—  Ideas y valores[34] and Cuadernos de Filosofía y Letras—in which analytic (and non-analytic) works are published. Rubén Sierra Mejia, in the second half of the 1960s, introduced in Bogotá courses and translations of some classical works within the analytic tradition, and published his articles in a book, Apreciación de la Filosofía Analítica (1987). At the University of Valle (Cali), Adolfo León Lobos introduced argumentation theory and ordinary language philosophy. In the 1980s there was much activity in ordinary language  philosophy.[35] Juan José Botero is known for his work focused on the common origins of the phenomenological and the analytic traditions, examining the correspondence between Husserl and Frege and publishing works on consciousness, propositional attitudes, sense and reference. There are many other contemporary Colombian philosophers who are making significant contributions within the analytic  tradition.[36]