Wahyuni, Vera. “Aiken Index Analysis to Determine The Contents Validity of Project Assessment Instrument in Learning Islamic Religion and Character in the Independent Curriculum”. Jurnal Sustainable 6, no. 2 (December 13, 2023): 565-569. Accessed April 23, 2025. http://lp2msasbabel.ac.id/jurnal/index.php/sus/article/view/4043.