Hatem , A. . . and Ebraheem, K. . . (2017) “Effectiveness of Universal Concept of Mental Arithmetic System (UCMAS) In The Developing Of Visual Thinking Among Fourth Grade Students (Quasi- Experimental Study In Private Schools At Lattakia)”, Tishreen University Journal- Arts and Humanities Sciences Series, 38(1). Available at: https://journal.tishreen.edu.sy/index.php/humlitr/article/view/2318 (Accessed: 21May2024).