علي عسّاف, سليمان الخضر and ميساء شعبان (2022) “A study of gravitational field equation in general relativity”, Tishreen University Journal -Basic Sciences Series, 44(1), pp. 131–142. Available at: https://journal.tishreen.edu.sy/index.php/bassnc/article/view/13326 (Accessed: 23May2024).