García, J., De Lera, V., Lacambra, D., Gimeno, F. and Alesanco, Álvaro (2021) “Design and Development of an Android App Based on Firebase in the Study of Unsportsmanlike Behaviors in Grassroots Tennis Competitions”, Journal of Mobile Multimedia, 17(4), pp. 603–636. doi: 10.13052/jmm1550-4646.1746.