WASET
    Paulo R. M. de Andrade and  Adriano B. Albuquerque and  Otávio F. Frota and  Robson V. Silveira and  Fátima A. da Silva,  Virtualizing Attendance and Reducing Impacts on the Environment with a Mobile Application.   journal   = {International Journal of Information and Communication Engineering}, [online]. World Academy of Science, Engineering and Technology.
    November 2015, vol. 104(8). 2028 - 2033
    [viewed 24 April 2024]. Available from: https://publications.waset.org/pdf/10003229.