Abdel-Salam Al-Hafidh, Mahmood, and Zainab Abdel-Salam Mohammed. 2014. “The Effect of Chemistry Teaching According to Learning Dimensions Model on the Development of Chemical Concepts and the Meta-Cognitive Skills for First Grade Secondary Students”. College of Basic Education Research Journal 13 (1):79-120. https://stats.uomosul.edu.iq/index.php/berj/article/view/39522.