Vázquez E, Fombona J, Fernández A. Virtual attendance: Analysis of an audiovisual over IP system for distance learning in the Spanish Open University (UNED). IRRODL [Internet]. 2013 Jul. 5 [cited 2024 Nov. 21];14(3):402-26. Available from: https://www.irrodl.org/index.php/irrodl/article/view/1430