Ritonga, A.K. (2016) “Effects of Cooperative Learning Method Type Stad, Language Aptitude, and Intelligence on the Achievement English Hotel at Medan Tourism Academy”, International Journal of Social Sciences & Educational Studies, 3(2), pp. 128–139. Available at: https://ijsses.tiu.edu.iq/index.php/ijsses/article/view/578 (Accessed: 1 May 2026).