Extraction of Nb from cassiterite flotation residues by acid calcination and water solubilization - Gutierrez, George Orlando Martinez; Machaca, Darwin Michell Cheje; Garjulli, Franco; Pereira, Bárbara Rocha; Mayta Armas, Angie Fiorella; Espinosa, Denise Crocce Romano; Tenório, Jorge Alberto Soares; Baltazar, Marcela dos Passos Galluzzi (Journal of Sustainable Metallurgy, 2025)