Camargo, J. E., V. Vargas-Calderon, N. Vargas, and L. Calderón-Benavides. “Sentiment Polarity Classification of Tweets Using a Extended Dictionary”. Inteligencia Artificial, vol. 21, no. 62, Sept. 2018, pp. 1-12, doi:10.4114/intartif.vol21iss62pp1-12.