2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/59968We introduce three-variable analogues of the theta series of Borwein and Borwein. We prove various identities involving these theta series including a generalization of the cubic identity of Borwein and Borwein.7 pages, LaTeX, submitted to The Ramanujan JournalNumber Theory11F27 (primary); 11B65; 11F11 (secondary)text