SIDDIQA, Ayesha. A Study of Students Perception about Opportunity Cost of Virtual Learning: An Empirical Evidence from Punjab, Pakistan. International Journal of Advanced Social Studies, [S. l.], v. 3, n. 2, p. 60–71, 2023. DOI: 10.70843/ijass.2023.03022. Disponível em: https://explorescholar.org/journals/index.php/IJASS/article/view/22.. Acesso em: 26 oct. 2025.