Gadelha de Carvalho, S. M., and P. Martins Pio. “The Category of Praxis in Pedagogy of the Oppressed: Meanings and Implications for a Libertarian Education”. Brazilian Journal of Pedagogical Studies , Vol. 98, no. 249, Aug. 2017, doi:10.24109/2176-6681.rbep.98i249.2729.