et. al., Saja Hamid Hantoush Al-Rubaie,. “The Extent to Which the 6th Grade Science Textbook Includes 21st Century Skills”. Turkish Journal of Computer and Mathematics Education (TURCOMAT) 12, no. 11 (May 10, 2021): 358–368. Accessed May 4, 2024. https://turcomat.org/index.php/turkbilmat/article/view/5886.