Alobeidani, M. J. M., & Haron, S. C. (2022). Degree of the availability of the 21st century skills in the social studies textbooks of the twelfth grade of post-basic education in Sultanate of Oman. Journal of Curriculum and Teaching Methodology, 1(8), 61-85. https://doi.org/10.26389/AJSRP.D200222