MORISHIMA, A. Volunteer-Based Crowdsourcing with Crowd4U. Proceedings of the AAAI Conference on Human Computation and Crowdsourcing, [S. l.], v. 2, n. 1, 2014. Disponível em: https://ojs.aaai.org/index.php/HCOMP/article/view/13203. Acesso em: 12 jun. 2021.