Hamdani, Muhammad, et al. “Demonstration and Experiment on Archaebacteria and Eubacteria: Effectiveness for Cognitive Learning Outcomes (CLO) Based on Critical Thinking Skill”. Biosfer: Jurnal Pendidikan Biologi, vol. 13, no. 1, May 2020, pp. 75-85, doi:10.21009/biosferjpb.v13n1.75-85.