Sulastri, Malahayati Rahayu, et al. “The Development of Learning Media and Critical Thinking Skill Instrument Based on 5E Learning Cycle Model on Harmonic Vibration Material”. Jurnal Pijar Mipa, vol. 16, no. 4, Sept. 2021, pp. 466-72, doi:10.29303/jpm.v16i4.2847.