Saputra, Kormil, 		Inayah, Rahmatun, 		Aminy, Ika Umratul Asni, 		Ardianto, Teguh, AND 		Kurniawidi, Dian W..
" Electronic Properties of Fe3-xCoxO4 (x = 0.25 and 0.375) Synthesized from Natural Iron Sand: Evaluation of Band Gap and Urbach Tail" <em>Jurnal Teras Fisika: Teori, Modeling, dan Aplikasi Fisika</em> [Online], Volume 8 Number 2 (22 November 2025)