Siswoyo, Siswoyo. “Development of Teacher Guidebook for Photoelectric Effects Instructional Using Predict-Observe-Explain Strategy With PhET Interactive Simulation”. Jurnal Penelitian & Pengembangan Pendidikan Fisika 5, no. 2 (November 5, 2019): 133 - 144. Accessed March 29, 2024. https://journal.unj.ac.id/unj/index.php/jpppf/article/view/12754.