Andriani, Feni, Meti Indrowati, and Bowo Sugiharto. “Analysis Items of the Four-Tier Immune System Multiple Choice Test Instrument Using Rasch Model”. Biosfer: Jurnal Pendidikan Biologi 14, no. 1 (April 30, 2021): 99-119. Accessed December 14, 2025. http://103.8.12.212:33180/unj/index.php/biosfer/article/view/18020.