Ramdani, Dani, et al. “Fostering 21st-Century Skills: The Effectiveness of Ricosre and Digital Flipbooks in Enhancing Student Collaboration in Biology Learning”. Biosfer: Jurnal Pendidikan Biologi, vol. 18, no. 2, Nov. 2025, pp. 424-36, doi:10.21009/biosferjpb.59320.