Twitter Mining for Multiclass Classification Events of Traffic and Pollution. - Verónica Chamorro; Richard Rivera; José Varela Aldás; David Castillo Salazar; Carlos Borja-Galeas; César Guevara; Hugo Arias-Flores; Washington Fierro-Saltos; Jairo Hidalgo-Guijarro; Marco Yandún-Velasteguí (IHSED, 2019)