Sirianni, G. R., K. Mendel, E. Y. Nagasawa, and J. R. Schoffen. “The Outcomes of Acervo Celpe-Bras for Teaching, Learning, Assessment and Research in Portuguese As an Additional Language”. BELT - Brazilian English Language Teaching Journal, vol. 10, no. 1, Aug. 2019, p. e33233, doi:10.15448/2178-3640.2019.1.33233.