Tantuico, Kathleen D. 2020. “The 2020 Re-Excavation of Callao Cave, Northeastern Luzon, the Philippines | Ang Muling Pagsusuring Archaeological Sa Callao Cave, Hilagang-Silangang Luzon, Pilipinas Sa 2020”. SPAFA Journal 4 (July). https://doi.org/10.26721/spafajournal.v4i0.638.